Precursor Compounds for Molecular Coatings

ABSTRACT

and an additive, wherein the variables m, n, q, r, Ra, Rb, R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12 and R13 are defined herein. The protective coatings formed from the compositions can be used to prevent food spoilage due to, for instance, moisture loss, oxidation, or infection by a foreign pathogen.

RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/330,403, filed Sep. 15, 2016 which claims the benefit under 35 U.S.C§ 119(e) of U.S. Provisional Patent Application Ser. No. 62/219,372,filed Sep. 16, 2015, the disclosure of which is incorporated herein byreference in its entirety.

TECHNICAL FIELD

The present disclosure relates to compositions that can be used to formprotective coatings on a substrate. The disclosure also relates to theprotective coatings themselves.

BACKGROUND

Common agricultural products are susceptible to degradation anddecomposition (i.e., spoilage) when exposed to the environment. Suchagricultural products can include, for example, eggs, fruits,vegetables, produce, seeds, nuts, flowers, and/or whole plants(including their processed and semi-processed forms). Non-agriculturalproducts (e.g., vitamins, candy, etc.) are also vulnerable todegradation when exposed to the ambient environment. The degradation ofthe agricultural products can occur via abiotic means as a result ofevaporative moisture loss from an external surface of the agriculturalproducts to the atmosphere and/or oxidation by oxygen that diffuses intothe agricultural products from the environment and/or mechanical damageto the surface and/or light-induced degradation (i.e.,photodegradation). Furthermore, biotic stressors such as, for example,bacteria, fungi, viruses, and/or pests can also infest and decompose theagricultural products.

Conventional approaches to preventing degradation, maintaining quality,and increasing the life of agricultural products include refrigerationand/or special packaging. Refrigeration can require capital-intensiveequipment, demands constant energy expenditure, can cause damage orquality loss to the product if not carefully controlled, must beactively managed, and its benefits can be lost upon interruption of atemperature-controlled supply chain. Special packaging can also requireexpensive equipment, consume packaging material, increase transportationcosts, and require active management. Despite the benefits that can beafforded by refrigeration and special packaging, the handling andtransportation of the agricultural products can cause surface abrasionor bruising that is aesthetically displeasing to the consumer and servesas points of ingress for bacteria and fungi. Moreover, the expensesassociated with such approaches can add to the cost of the agriculturalproduct.

The cells that form the aerial surface of most plants (such as higherplants) include an outer envelope or cuticle, which provides varyingdegrees of protection against water loss, oxidation, mechanical damage,photodegradation, and/or biotic stressors, depending upon the plantspecies and the plant organ (e.g., fruit, seeds, bark, flowers, leaves,stems, etc.). Cutin, which is a biopolyester derived from cellularlipids, forms the major structural component of the cuticle and servesto provide protection to the plant against environmental stressors (bothabiotic and biotic). The thickness, density, as well as the compositionof the cutin (i.e., the different types of monomers that form the cutinand their relative proportions) can vary by plant species, by plantorgan within the same or different plant species, and by stage of plantmaturity. The cutin-containing portion of the plant can also containadditional compounds (e.g., epicuticular waxes, phenolics, antioxidants,colored compounds, proteins, polysaccharides, etc.). This variation inthe cutin composition as well as the thickness and density of the cutinlayer between plant species and/or plant organs and/or a given plant atdifferent stages of maturation can lead to varying degrees of resistancebetween plant species or plant organs to attack by environmentalstressors (i.e., water loss, oxidation, mechanical injury, and light)and/or biotic stressors (e.g., fungi, bacteria, viruses, insects, etc.).

SUMMARY

Described herein are compositions that can be used to form protectivecoatings on substrates. The coatings can be used to protect thesubstrates, e.g., food and/or agricultural products, from spoilageand/or decomposition due to factors such as moisture loss, oxidation,mechanical degradation, photodegradation, and fungal growth. Thecompositions can be made from monoacylglycerides similar to those thatalso make up the cutin layer of the plant cuticle.

Accordingly, in one aspect of the present disclosure, a compositioncomprises a 2-monoacylglyceride compound of the Formula I:

wherein:

each R^(a) is independently —H or —C₁-C₆alkyl;

each R^(b) is independently selected from —H, —C₁-C₆alkyl, or —OH;

R¹, R², R⁵, R⁶, R⁹, R¹⁰, R¹¹, R¹² and R¹³ are each independently, ateach occurrence, —H, —OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, halogen, —C₁-C₆alkyl,—C₂-C₆alkenyl, —C₂-C₆alkynyl, —C₃-C₇cycloalkyl, aryl, or heteroaryl,wherein each alkyl, alkenyl, alkynyl, cycloalkyl, aryl, or heteroaryl isoptionally substituted with one or more —OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, orhalogen;

R³, R⁴, R⁷, and R⁸ are each independently, at each occurrence, —H,—OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, halogen, —C₁-C₆alkyl, —C₂-C₆alkenyl,—C₂-C₆alkynyl, —C₃-C₇cycloalkyl, aryl, or heteroaryl wherein each alkyl,alkynyl, cycloalkyl, aryl, or heteroaryl is optionally substituted withone or more —OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, or halogen; or

R³ and R⁴ can combine with the carbon atoms to which they are attachedto form a C₃-C₆ cycloalkyl, a C₄-C₆cycloalkenyl, or 3- to 6-memberedring heterocycle; and/or

R⁷ and R⁸ can combine with the carbon atoms to which they are attachedto form a C₃-C₆ cycloalkyl, a C₄-C₆cycloalkenyl, or 3- to 6-memberedring heterocycle;

R¹⁴ and R¹⁵ are each independently, at each occurrence, —H, —C₁-C₆alkyl,—C₂-C₆alkenyl, or —C₂-C₆alkynyl;

the symbol

represents a single bond or a cis or trans double bond;

n is 0, 1, 2, 3, 4, 5, 6, 7 or 8;

m is 0, 1, 2 or 3;

q is 0, 1, 2, 3, 4 or 5; and

r is 0, 1, 2, 3, 4, 5, 6, 7 or 8; and

an additive;

wherein a mass ratio (or a molar ratio) of the additive to the compoundof Formula I is in a range of about 0.1 to about 1.

The additive of any of the compositions described herein can be anyorganic compound, including 1-monoacylglycerides, fatty acids, esters,amides, amines, thiols, carboxylic acids, ethers, aliphatic waxes,alcohols, salts (inorganic and organic), or combinations thereof.

In one or more embodiments, the additive is a 1-monoacylglyceridecompound of Formula II:

wherein:

each R^(a) is independently —H or —C₁-C₆alkyl;

each R^(b) is independently selected from —H, —C₁-C₆alkyl, or —OH;

R¹, R², R⁵, R⁶, R⁹, R¹⁰, R¹¹, R¹² and R¹³ are each independently, ateach occurrence, —H, —OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, halogen, —C₁-C₆alkyl,—C₂-C₆alkenyl, —C₂-C₆alkynyl, —C₃-C₇cycloalkyl, aryl, or heteroaryl,wherein each alkyl, alkenyl, alkynyl, cycloalkyl, ₀aryl, or heteroarylis optionally substituted with one or more —OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, orhalogen;

R³, R⁴, R⁷, and R⁸ are each independently, at each occurrence, —H,—OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, halogen, —C₁-C₆alkyl, —C₂-C₆alkenyl,—C₂-C₆alkynyl, —C₃-C₇cycloalkyl, aryl, or heteroaryl wherein each alkyl,alkenyl, alkynyl, cycloalkyl, aryl, or heteroaryl is optionallysubstituted with one or more —OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, or halogen; or

R³ and R⁴ can combine with the carbon atoms to which they are attachedto form a C₃-C₆ cycloalkyl, a C₄-C₆cycloalkenyl, or 3- to 6-memberedring heterocycle; and/or

R⁷ and R⁸ can combine with the carbon atoms to which they are attachedto form a C₃-C₆ cycloalkyl, a C₄-C₆cycloalkenyl, or 3- to 6-memberedring heterocycle;

R¹⁴ and R¹⁵ are each independently, at each occurrence, —H, —C₁-C₆alkyl,—C₂-C₆alkenyl, or —C₂-C₆alkynyl;

the symbol

represents a single bond or a cis or trans double bond;

n is 0, 1, 2, 3, 4, 5, 6, 7 or 8;

m is 0, 1, 2 or 3;

q is 0, 1, 2, 3, 4 or 5; and

r is 0, 1, 2, 3, 4, 5, 6, 7 or 8.

In another aspect of the present disclosure, a solution comprises acompound Formula I and an additive (e.g., a compound of Formula II),wherein the molar ratio or mass ratio of the additive to the compound ofFormula I is in a range of 0.1 to 1, and wherein the additive and thecompound of Formula I are dissolved in a solvent at a concentration ofat least about 0.5 mg/mL.

In another aspect, the present disclosure provides for the use of acomposition comprising Formula I and an additive (e.g., a compound ofFormula II) to prevent spoilage of an agricultural substrate (e.g., afood).

In another aspect of the present disclosure, a composition includes acompound of Formula I:

wherein:

each R^(a) is independently —H or —C₁-C₆alkyl;

each R^(b) is independently selected from —H, —C₁-C₆alkyl, or —OH;

R¹, R², R⁵, R⁶, R⁹, R¹⁰, R¹¹, R¹² and R¹³ are each independently, ateach occurrence, —H, —OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, halogen, —C₁-C₆alkyl,—C₂-C₆alkenyl, —C₂-C₆alkynyl, —C₃-C₇cycloalkyl, aryl, or heteroaryl,wherein each alkyl, alkenyl, alkynyl, cycloalkyl, aryl, or heteroaryl isoptionally substituted with one or more —OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, orhalogen;

R³, R⁴, R⁷, and R⁸ are each independently, at each occurrence, —H,—OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, halogen, —C₁-C₆alkyl, —C₂-C₆alkenyl,—C₂-C₆alkynyl, —C₃-C₇cycloalkyl, aryl, or heteroaryl wherein each alkyl,alkynyl, cycloalkyl, aryl, or heteroaryl is optionally substituted withone or more —OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, or halogen; or

R³ and R⁴ can combine with the carbon atoms to which they are attachedto form a C₃-C₆ cycloalkyl, a C₄-C₆cycloalkenyl, or 3- to 6-memberedring heterocycle; and/or

R⁷ and R⁸ can combine with the carbon atoms to which they are attachedto form a C₃-C₆ cycloalkyl, a C₄-C₆cycloalkenyl, or 3- to 6-memberedring heterocycle;

R¹⁴ and R¹⁵ are each independently, at each occurrence, —H, —C₁-C₆alkyl,—C₂-C₆alkenyl, or —C₂-C₆alkynyl;

the symbol

represents a single bond or a cis or trans double bond;

n is 0, 1, 2, 3, 4, 5, 6, 7 or 8;

m is 0, 1, 2 or 3;

q is 0, 1, 2, 3, 4 or 5; and

r is 0, 1, 2, 3, 4, 5, 6, 7 or 8; and

at least two additives;

wherein a molar ratio of the additives to the compound of Formula I isabout 1 or higher.

In still another aspect of the present disclosure, a compositionincludes a compound of Formula II:

wherein:

each R^(a) is independently —H or —C₁-C₆alkyl;

each R^(b) is independently selected from —H, —C₁-C₆alkyl, or —OH;

R¹, R², R⁵, R⁶, R⁹, R¹⁰, R¹¹, R¹² and R¹³ are each independently, ateach occurrence, —H, —OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, halogen, —C₁-C₆alkyl,—C₂-C₆alkenyl, —C₂-C₆alkynyl, —C₃-C₇cycloalkyl, aryl, or heteroaryl,wherein each alkyl, alkenyl, alkynyl, cycloalkyl, ₀aryl, or heteroarylis optionally substituted with one or more —OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, orhalogen;

R³, R⁴, R⁷, and R⁸ are each independently, at each occurrence, —H,—OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, halogen, —C₁-C₆alkyl, —C₂-C₆alkenyl,—C₂-C₆alkynyl, —C₃-C₇cycloalkyl, aryl, or heteroaryl wherein each alkyl,alkenyl, alkynyl, cycloalkyl, aryl, or heteroaryl is optionallysubstituted with one or more —OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, or halogen; or

R³ and R⁴ can combine with the carbon atoms to which they are attachedto form a C₃-C₆ cycloalkyl, a C₄-C₆cycloalkenyl, or 3- to 6-memberedring heterocycle; and/or

R⁷ and R⁸ can combine with the carbon atoms to which they are attachedto form a C₃-C₆ cycloalkyl, a C₄-C₆cycloalkenyl, or 3- to 6-memberedring heterocycle;

R¹⁴ and R¹⁵ are each independently, at each occurrence, —H, —C₁-C₆alkyl,—C₂-C₆alkenyl, or —C₂-C₆alkynyl;

the symbol

represents a single bond or a cis or trans double bond;

n is 0, 1, 2, 3, 4, 5, 6, 7 or 8;

m is 0, 1, 2 or 3;

q is 0, 1, 2, 3, 4 or 5; and

r is 0, 1, 2, 3, 4, 5, 6, 7 or 8; and

a first additive and a second additive; wherein

the compound of Formula II, the first additive, and the second additiveare each different from one another; and

the first and second additives are each independently selected from thegroup of compounds consisting of 1-monoacylglycerides, fatty acids,esters, amides, amines, thiols, carboxylic acids, ethers, aliphaticwaxes, alcohols, organic salts, and inorganic salts.

Compositions and solutions described herein can each include one or moreof the following features, either alone or in combination with oneanother. The symbol

can represent a single bond, a double bond, or a double bond between R³and R⁴. R¹¹ can be —OH. n can be 7, and R³ and/or R⁴ can be —OH. R³ andR⁴ can combine with the carbon atoms to which they are attached to forman epoxide. R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, R¹⁰, R¹¹, R¹², and R¹³can each be —H. The mass ratio of the additive to the compound ofFormula I can be in a range of about 0.1 to about 1, about 0.1 to about0.5, about 0.2 to about 0.4, about 0.25 to about 0.35, about 0.3 toabout 0.7, about 0.4 to about 0.6, about 0.45 to about 0.55, about 0.1to about 1, about 0.1 to about 0.5, about 0.2 to about 0.4, about 0.25to about 0.35, about 0.3 to about 0.7, about 0.4 to about 0.6, or about0.45 to about 0.55.

The composition or solution can include an additive. The composition orsolution can include a first additive and a second additive. Thecomposition or solution can include at least two additives. The firstadditive can be different from the second additive. The additive, firstadditive, or second additive can be a compound of Formula II, whereFormula II is as previously described. The additive, first additive, orsecond additive can be a fatty acid. The additive, first additive, orsecond additive can be an ester. The first additive can be a fatty acidand the second additive can be a compound of Formula II, where FormulaII is as previously described. The composition can comprise less thanabout 10% of proteins, polysaccharides, phenols, lignans, aromaticacids, terpenoids, flavonoids, carotenoids, alkaloids, alcohols,alkanes, and aldehydes. The additive can be a fatty acid having a carbonchain length that is the same as a carbon chain length of the compoundof Formula I. The additive can be a fatty acid having a carbon chainlength that is different from a carbon chain length of the compound ofFormula I. The additive can be a fatty acid having a carbon chain lengththat is the same as a carbon chain length of the compound of Formula II.The additive can be a fatty acid having a carbon chain length that isdifferent from a carbon chain length of the compound of Formula II. Theat least two additives can each be independently selected from the groupof compounds consisting of 1-monoacylglycerides, fatty acids, esters,amides, amines, thiols, carboxylic acids, ethers, aliphatic waxes,alcohols, organic salts, and inorganic salts. The first and secondadditives can each be independently selected from the group of compoundsconsisting of 1-monoacylglycerides, fatty acids, esters, amides, amines,thiols, carboxylic acids, ethers, aliphatic waxes, alcohols, organicsalts, and inorganic salts. The first and second additives can each befatty acids. The first additive can be palmitic acid and the secondadditive can be oleic acid. A carbon chain length of the compound ofFormula I can be the same as a carbon chain length of the compound ofFormula II. A carbon chain length of the compound of Formula I can bedifferent from a carbon chain length of the compound of Formula II. Asused herein, the term “carbon chain length” is understood as the portionof a compound of Formula I, Formula II, Formula III or a fatty acidadditive that is bound to the carbonyl carbon. That is, the carbon chainlength can be defined by the variables m, n, q and r.

The composition can be soluble in ethanol at a range of at least 20mg/mL, at least 50 mg/mL, at least 100 mg/mL, at least about 20 mg/mL,at least about 50 mg/mL, or at least about 100 mg/mL. The compositioncan be soluble in water at a range of at least 20 mg/mL, at least 50mg/mL, at least 100 mg/mL, at least about 20 mg/mL, at least about 50mg/mL, or at least about 100 mg/mL. The composition can be soluble in asolvent including ethanol and water at a range of at least 20 mg/mL, atleast 50 mg/mL, at least 100 mg/mL, at least about 20 mg/mL, at leastabout 50 mg/mL, or at least about 100 mg/mL. The solvent can be at least25% water by volume, at least 50% water by volume, at least 75% water byvolume, at least 90% water by volume, less than 35% water by volume, atleast about 25% water by volume, at least about 50% water by volume, atleast about 75% water by volume, at least about 90% water by volume, orless than about 35% water by volume. The composition can be a solid atabout 25° C. and about 1 atmosphere of pressure, and optionally thesolid can include crystals having an average diameter less than about 2millimeters.

The concentration of the solute in the solution can be at least 0.5mg/mL, at least 1 mg/mL, at least 5 mg/mL, at least 10 mg/mL, at least20 mg/mL, at least about 0.5 mg/mL, at least about 1 mg/mL, at leastabout 5 mg/mL, at least about 10 mg/mL, or at least about 20 mg/mL. Theconcentration of the solute in the solution can be below the saturationlimit. The solvent can comprise, water and/or ethanol. The compositionor solution can further comprise an additional agent selected from apigment or an odorant.

In another aspect of the present disclosure, a method of forming acoating on a substrate comprises: (i) providing a composition comprisinga compound Formula I, the composition being dissolved in a solvent toform a solution; (ii) applying the solution to a surface of thesubstrate; and (iii) causing the composition to re-solidify on thesurface to form the coating. In some embodiments, the compositionfurther comprises an additive (e.g., a compound of Formula II). A massratio of the additive to the compound of Formula I can be in a range of0.1 to 1.

In another aspect of the disclosure, a method of forming a coating on asubstrate comprises: (i) providing a composition comprising a compoundFormula I, the composition being dissolved in a solvent to form asolution; (ii) applying the solution to a surface of the substrate; and(iii) causing the composition to re-solidify on the surface to form thecoating. The coating can be optically transparent throughout, or canhave an average transmittance of at least 60% for light in the visiblerange. In some embodiments, an entirety of the coating has atransmittance of at least 60% for light in the visible range.Accordingly, the coating can be free of visible residues larger than0.25 μm² in area.

In another aspect of the present disclosure, a method of forming acoating on a substrate comprises: (i) providing a composition comprisinga compound of Formula II, the composition being dissolved in a solventto form a solution; (ii) applying the solution to a surface of thesubstrate; and (iii) causing the composition to re-solidify on thesurface to form the coating. The coating can be optically transparentthroughout, or can have an average transmittance of at least 60% forlight in the visible range. In some embodiments, an entirety of theprotective layer has a transmittance of at least 60% for light in thevisible range. Accordingly, the protective layer can be free of visibleresidues larger than 0.25 μm² in area.

In another aspect of the present disclosure, a method for producing acomposition comprising a compound of Formula I and an additive includes:

(i) providing a compound of Formula III:

wherein:

X is O or NR¹;

R¹, R², R⁵, R⁶, R⁹, R¹⁰, R¹¹, R¹² and R¹³ are each independently, ateach occurrence, —H, —OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, halogen, —C₁-C₆alkyl,—C₂-C₆alkenyl, —C₂-C₆alkynyl, —C₃-C₇cycloalkyl, aryl, or heteroaryl,wherein each alkyl, alkenyl, alkynyl, cycloalkyl, aryl, or heteroaryl isoptionally substituted with one or more —OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, orhalogen;

R³, R⁴, R⁷, and R⁸ are each independently, at each occurrence, —H,—OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, halogen, —C₁-C₆alkyl, —C₂-C₆alkenyl,—C₂-C₆alkenyl, —C₂-C₆alkynyl, —C₃-C₇cycloalkyl, aryl, or heteroarylwherein each alkyl, alkynyl, cycloalkyl, aryl, or heteroaryl isoptionally substituted with one or more —OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, orhalogen; or

R³ and R⁴ can combine with the carbon atoms to which they are attachedto form a C₃-C₆ cycloalkyl, a C₄-C₆cycloalkenyl, or 3- to 6-memberedring heterocycle; and/or

R⁷ and R⁸ can combine with the carbon atoms to which they are attachedto form a C₃-C₆ cycloalkyl, a C₄-C₆cycloalkenyl, or 3- to 6-memberedring heterocycle;

R¹⁴ and R¹⁵ are each independently, at each occurrence, —H, —C₁-C₆alkyl,—C₂-C₆alkenyl, or —C₂-C₆alkynyl;

the symbol

represents a single bond or a cis or trans double bond;

n is 0, 1, 2, 3, 4, 5, 6, 7 or 8;

m is 0, 1, 2 or 3;

q is 0, 1, 2, 3, 4 or 5; and

r is 0, 1, 2, 3, 4, 5, 6, 7 or 8; and

R is selected from —H, —C₁-C₆alkyl, —C₂-C₆alkenyl, —C₂-C₆alkynyl,—C₃-C₇cycloalkyl, aryl, or heteroaryl;

(ii) converting the compound of Formula III to produce a compound ofFormula I

wherein:

each R^(a) is independently —H or —C₁-C₆alkyl;

each R^(b) is independently selected from —H, —C₁-C₆alkyl, or —OH;

R¹, R², R⁵, R⁶, R⁹, R¹⁰, R¹, R¹² and R¹³ are each independently, at eachoccurrence, —H, —OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, halogen, —C₁-C₆alkyl,—C₂-C₆alkenyl, —C₂-C₆alkynyl, —C₃-C₇cycloalkyl, aryl, or heteroaryl,wherein each alkyl, alkenyl, alkynyl, cycloalkyl, aryl, or heteroaryl isoptionally substituted with one or more —OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, orhalogen;

R³, R⁴, R⁷, and R⁸ are each independently, at each occurrence, —H,—OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, halogen, —C₁-C₆alkyl, —C₂-C₆alkenyl,—C₂-C₆alkenyl, —C₂-C₆alkynyl, —C₃-C₇cycloalkyl, aryl, or heteroarylwherein each alkyl, alkynyl, cycloalkyl, aryl, or heteroaryl isoptionally substituted with one or more —OR¹⁴, —NR¹⁴R¹⁵, —SR¹⁴, orhalogen; or

R³ and R⁴ can combine with the carbon atoms to which they are attachedto form a C₃-C₆ cycloalkyl, a C₄-C₆cycloalkenyl, or 3- to 6-memberedring heterocycle; and/or

R⁷ and R⁸ can combine with the carbon atoms to which they are attachedto form a C₃-C₆ cycloalkyl, a C₄-C₆cycloalkenyl, or 3- to 6-memberedring heterocycle;

R¹⁴ and R¹⁵ are each independently, at each occurrence, —H, —C₁-C₆alkyl,—C₂-C₆alkenyl, or —C₂-C₆alkynyl;

the symbol

represents a single bond or a cis or trans double bond;

n is 0, 1, 2, 3, 4, 5, 6, 7 or 8;

m is 0, 1, 2 or 3;

q is 0, 1, 2, 3, 4 or 5; and

r is 0, 1, 2, 3, 4, 5, 6, 7 or 8;

(iii) combining the compound of Formula I with an additive such that amolar ratio of the additive to the compound of Formula I is in a rangeof about 0.1 to 1.

In another aspect of the present disclosure, a method of forming aprotective coating includes (i) providing a solution comprising a solutedissolved in a solvent, the solute comprising a composition of compoundsselected from the group consisting of 1-monoacylglycerides, fatty acids,esters, amides, amines, thiols, carboxylic acids, ethers, aliphaticwaxes, alcohols, salts (inorganic and organic), and compounds of FormulaI; (ii) applying the solution to a surface of a substrate; and (iii)causing the solute to solidify on the surface and form the protectivecoating. The protective coating can have a thickness greater than 0.1microns. The protective layer can have an average transmittance of atleast 60% for light in the visible range.

In another aspect, a method of forming a protective coating includes (i)providing a solution comprising a solute dissolved in a solvent, thesolute comprising a compound of Formula I; (ii) applying the solution toa surface of a substrate, and (iii) causing the solute to solidify onthe surface and form the protective coating. The protective coating caninclude the compound of Formula I and can be characterized as being freeof free of visible precipitates or other visible residues larger than0.25 μm² in area.

In another aspect of the present disclosure, a method for reducing foodspoilage comprises coating a food substrate with a compositioncomprising Formula I and an additive in a mass or molar ratio of 0.1to 1. In some embodiments, the additive is a compound of Formula II asdescribed above.

In another aspect of the present disclosure, a method of protectingharvested produce comprises providing a solution including a solutedissolved in a solvent, and applying the solution to a surface of theharvested produce to form a coating over the produce. The coating can beformed from the solute and can be less than 3 microns thick, and thecoating can serve to reduce a rate of mass loss of the harvested produceby at least 10%.

In another aspect of the present disclosure, a solution comprising acompound of Formula I and an additive is disclosed, wherein the molarratio of the additive to the compound of Formula I is in a range ofabout 0.1 to 1; and wherein the additive and the compound of Formula Iare dissolved in a concentration of at least about 0.5 mg/mL.

In another aspect of the present disclosure, the compounds describedherein can be used to form a protective coating on a substrate. Thesubstrate can be an agricultural product, and the coating can helpreduce spoilage of the agricultural product.

Methods described herein can each include at least one or more of thefollowing features, either alone or in combination with one another. Thecomposition can be dissolved in the solution at a concentration of atleast 0.5 mg/mL or at least 1 mg/mL. The dissolving is performed at atemperature in the range of about 0° C. to about 40° C. Theconcentration of the solute in the solution can be below the saturationlimit. The solvent can comprise water and/or ethanol. The solvent can beat least 25% water by volume, at least 50% water by volume, at least 75%water by volume, at least 90% water by volume, less than 35% water byvolume, at least about 25% water by volume, at least about 50% water byvolume, at least about 75% water by volume, at least about 90% water byvolume, or less than about 35% water by volume.

Causing the composition to re-solidify can include removing (e.g.,evaporating) the solvent to precipitate the composition. The compound ofFormula III can be an acid, an ester, or an amide. Converting thecompound of Formula III to produce a compound of Formula I can includeesterifying the acid of Formula III. Converting the compound of FormulaIII to produce a compound of Formula I can include transesterifying theester or amide of Formula III. Converting the compound of Formula III toproduce a compound of Formula I can include treating the compound ofFormula III with an alcohol and a base or acid. The base can be basicresin, sodium hydroxide, lithium hydroxide, potassium hydroxide, sodiumcarbonate, lithium carbonate, or potassium carbonate. The acid can bemethanesulfonic acid, sulfuric acid, toluenesulfonic acid, HCl, or anacidic resin. Converting the compound of Formula III to produce acompound of Formula I can include treating the compound of Formula IIIwith an enzyme.

BRIEF DESCRIPTION OF THE DRAWINGS

The patent or application file contains at least one drawing executed incolor. Copies of this patent or patent application publication withcolor drawing(s) will be provided by the Office upon request and paymentof the necessary fee.

FIG. 1 shows high resolution images of coated avocados having varyinglevels of visible residues on their surfaces.

FIG. 2 shows high resolution time lapse photographs of lemons, both withand without coatings formed of compounds described herein.

FIG. 3 is a normalized plot of the cross-sectional areas of the lemonsof FIG. 2 as a function of time.

FIG. 4 is a plot of average mass loss rates of strawberries, both withand without coatings formed of compounds described herein.

FIG. 5 shows high resolution time lapse photographs of strawberries,both with and without coatings formed of compounds described herein.

FIG. 6 is a plot of average mass loss rates of blueberries, both withand without coatings formed of 1-glycerol and 2-glycerol esters ofpalmitic acid.

FIG. 7 is a plot of average mass loss rates of blueberries, both withand without coatings formed of 1-glycerol and 2-glycerol esters ofstearic acid.

FIG. 8 is a plot of the percent mass loss of blueberries as a functionof time.

FIG. 9 shows high resolution photographs of blueberries, both with andwithout coatings formed of compounds described herein.

FIG. 10 shows high resolution time lapse photographs of bananas, bothwith and without coatings formed of compounds described herein.

FIG. 11 shows a plot of mass loss rates per day for finger limes coatedwith 1-glycerol and 2-glycerol esters of palmitic acid.

FIG. 12 shows a plot of the shelf life factor of avocados coated withcoatings formed of 2-glycerol esters of palmitic acid and 1-glycerolesters of myristic acid, palmitic acid, and stearic acid.

FIG. 13 shows a plot of the shelf life factor of avocados coated withcoatings formed of 2-glycerol esters of palmitic acid and myristic acid,palmitic acid, and stearic acid.

FIG. 14 shows a plot of the shelf life factor for avocados coated withcompositions comprising 2-glycerol esters of palmitic acid combined withethyl palmitate and oleic acid. FIG. 14 also shows a plot of the shelflife factor for avocados coated with compositions comprising 1-glycerolesters of stearic acid combined with myristic acid, palmitic acid, andstearic acid.

FIG. 15 shows a plot of the shelf life factor for avocados coated with1-glycerol esters of myristic acid, palmitic acid, and stearic acid incombination with myristic acid, palmitic acid, and stearic acid.

FIG. 16 shows a plot of the shelf life factor for avocados coated withmixtures of 1-glycerol esters of stearic acid, palmitic acid, andmyristic acid.

FIG. 17 shows a plot of the shelf life factor for avocados coated withmixtures comprising a combination of palmitic acid, 2-glycerol esters ofpalmitic acid, and 1-glycerol esters of stearic acid.

FIG. 18 shows a plot of the shelf life factor for avocados coated withmixtures comprising a combination of palmitic acid, oleic acid, and1-glycerol esters of stearic acid.

DETAILED DESCRIPTION

Described herein are compositions and solutions that can be used ascoatings for a substrate such as a food product or an agriculturalproduct. The compositions can comprise a compound of Formula I andoptionally an additive such as a compound of Formula II, as previouslydescribed. Alternatively, the compositions can include a compound ofFormula II and optionally an additive. The coatings can be formed, forexample, by dissolving the composition in a solvent to form a solution,applying the solution to the surface of the substrate being coated, andthen causing the solute to resolidify and form the coating, e.g., byevaporating the solvent and precipitating the solute.

The coatings and methods described herein offer a number of distinctfeatures and advantages over current methods of maintaining freshness ofagricultural products and food. For instance, the current disclosureprovides coatings that can prevent water loss and shield agriculturalproducts from threats such as bacteria, fungi, viruses and the like. Thecoatings can also protect, for instance, plants and food products fromphysical damage (e.g., bruising) and photodamage. Accordingly, thecurrent compositions, solutions, and coatings can be used to help storeagricultural products for extended periods of time without spoiling. Insome instances, the compositions and coatings allow for food to be keptfresh in the absence of refrigeration. The compositions and coatingsprovided herein can also be edible (i.e., the coatings can be non-toxicfor human consumption). In some embodiments, the coatings are tasteless,colorless, and/or odorless. In some preferred embodiments, the coatingsare made from the same chemical feedstocks that are naturally found inthe plant cuticle, (e.g., hydroxy and/or dihydroxy palmitic acids,and/or hydroxy or epoxy oleic and stearic acids) and can thus be organicand all-natural.

In addition to protecting substrates such as agricultural products andpreventing mass loss and water loss as described above, in many cases itcan be desirable for the coatings to be undetectable to the human eye,and/or to not cause any detectable changes in the physical appearance ofthe coated agricultural product. For example, coatings that precipitateor crystallize upon formation, or otherwise leave a residue upon thesurface of the coated product, can cause the coated product to appearsoiled or damaged, or to reduce the aesthetic appeal of the product.Consequently, the coated product may appear less desirable to a consumeras compared to a similar uncoated product. As such, in addition to beingeffective at preventing water/mass loss and/or protecting agriculturalproducts as described above, in many cases it is further desirable thatthe coating also not leave a visible residue and/or alter the physicalappearance of the coated product.

FIG. 1 illustrates the appearance and classification of visible residueson the surfaces of avocados after being coated with compositionsdescribed herein. Avocado 102 exhibited no visible residues. Avocado 112had only a small patch 114 (i.e., about 1-2 cm² or smaller, or occupyingabout 5% or less of the surface area of the avocado) of visibleresidues. Avocados with one small patch of visible residues wereclassified as having mild residues. Avocado 122 had a large patch 124(i.e., about 3-10 cm², or occupying about 5-25% of the surface area ofthe avocado) of visible residues. Avocados with one large patch ofvisible residues were classified as having moderate residues. Avocado132 had wide-spread visible residues covering most or all of thesurface. Such avocados were classified as having heavy residues.

As used herein, the term “substrate” refers to any object or materialover which a coating is formed or material is deposited. In particularimplementations, the substrate is edible to humans, and the coating isan edible coating. Examples of edible substrates include agriculturalproducts and foods such as fruits, vegetables, produce, seeds, nuts,beef, poultry, and seafood. Although in many embodiments the coatingsare formed over the entire outer surface of the substrate, in someembodiments the coatings can cover a portion of the outer surface of thesubstrate. The coatings can include apertures or porous regions whichexpose a portion of the outer surface of the substrate.

The term “alkyl” refers to a straight or branched chain saturatedhydrocarbon. C₁-C₆ alkyl groups contain 1 to 6 carbon atoms. Examples ofa C₁-C₆ alkyl group include, but are not limited to, methyl, ethyl,propyl, butyl, pentyl, isopropyl, isobutyl, sec-butyl and tert-butyl,isopentyl and neopentyl.

The term “alkenyl” means an aliphatic hydrocarbon group containing acarbon-carbon double bond and which may be straight or branched havingabout 2 to about 6 carbon atoms in the chain. Preferred alkenyl groupshave 2 to about 4 carbon atoms in the chain. Branched means that one ormore lower alkyl groups such as methyl, ethyl, or propyl are attached toa linear alkenyl chain. Exemplary alkenyl groups include ethenyl,propenyl, n-butenyl, and i-butenyl. A C₂-C₆ alkenyl group is an alkenylgroup containing between 2 and 6 carbon atoms. As defined herein, theterm “alkenyl” can include both “E” and “Z” or both “cis” and “trans”double bonds.

The term “alkynyl” means an aliphatic hydrocarbon group containing acarbon-carbon triple bond and which may be straight or branched havingabout 2 to about 6 carbon atoms in the chain. Preferred alkynyl groupshave 2 to about 4 carbon atoms in the chain. Branched means that one ormore lower alkyl groups such as methyl, ethyl, or propyl are attached toa linear alkynyl chain. Exemplary alkynyl groups include ethynyl,propynyl, n-butynyl, 2-butynyl, 3-methylbutynyl, and n-pentynyl. A C₂-C₆alkynyl group is an alkynyl group containing between 2 and 6 carbonatoms.

The term “cycloalkyl” means monocyclic or polycyclic saturated carbonrings containing 3-18 carbon atoms. Examples of cycloalkyl groupsinclude, without limitations, cyclopropyl, cyclobutyl, cyclopentyl,cyclohexyl, cycloheptanyl, cyclooctanyl, norboranyl, norborenyl,bicyclo[2.2.2]octanyl, or bicyclo[2.2.2]octenyl. A C₃-C₈ cycloalkyl is acycloalkyl group containing between 3 and 8 carbon atoms. A cycloalkylgroup can be fused (e.g., decalin) or bridged (e.g., norbornane).

The term “aryl” refers to cyclic, aromatic hydrocarbon groups that have1 to 2 aromatic rings, including monocyclic or bicyclic groups such asphenyl, biphenyl or naphthyl. Where containing two aromatic rings(bicyclic, etc.), the aromatic rings of the aryl group may be joined ata single point (e.g., biphenyl), or fused (e.g., naphthyl). The arylgroup may be optionally substituted by one or more substituents, e.g., 1to 5 substituents, at any point of attachment.

The term “heteroaryl” means a monovalent monocyclic or bicyclic aromaticradical of 5 to 12 ring atoms or a polycyclic aromatic radical,containing one or more ring heteroatoms selected from N, O, or S, theremaining ring atoms being C. Heteroaryl as herein defined also means abicyclic heteroaromatic group wherein the heteroatom(s) is selected fromN, O, or S. The aromatic radical is optionally substituted independentlywith one or more substituents described herein.

As used herein, the term “halo” or “halogen” means fluoro, chloro,bromo, or iodo.

The following abbreviations are used throughout. Hexadecanoic acid(i.e., palmitic acid) is abbreviated to PA. Octadecanoic acid (i.e.,stearic acid) is abbreviated to SA. Tetradecanoic acid (i.e., myristicacid) is abbreviated to MA. (9Z)-Octadecenoic acid (i.e., oleic acid) isabbreviated to OA. 1,3-dihydroxypropan-2-yl palmitate (i.e., 2-glyceropalmitate) is abbreviated to PA-2G. 1,3-dihydroxypropan-2-yloctadecanoate (i.e., 2-glycero stearate) is abbreviated to SA-2G.1,3-dihydroxypropan-2-yl tetradecanoic acid (i.e., 2-glycero myristate)is abbreviated to MA-2G. 1,3-dihydroxypropan-2-yl (9Z)-Octadecenoate(i.e., 2-glycero oleate) is abbreviated to OA-2G.2,3-dihydroxypropan-2-yl palmitate (i.e., 1-glycero palmitate) isabbreviated to PA-1G. 2,3-dihydroxypropan-2-yl octadecanoate (i.e.,1-glycero stearate) is abbreviated to SA-1G. 2,3-dihydroxypropan-2-yltetradecanoate (i.e., 1-glycero myristate) is abbreviated to MA-1G.2,3-dihydroxypropan-2-yl (9Z)-Octadecenoate (i.e., 1-glycero oleate) isabbreviated to OA-1G. Ethyl hexadecanoate (i.e., ethyl palmitate) isabbreviated to EtPA.

The compositions described herein can include compounds of the FormulaI:

wherein the definitions of R^(a), R^(b), R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸,R⁹, R¹⁰, R¹¹, R¹², R¹³, m, n, q, and r are as described above, andoptionally an additive.

In one or more embodiments, the additive is a compound of Formula II:

wherein the definitions of R^(a), R^(b), R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸,R⁹, R¹⁰, R¹¹, R¹², R¹³, m, n, q, and r are as described above.

In one or more embodiments, the symbol

represents a single bond. In one or more embodiments, the symbol

represents a double bond. In some embodiments, R¹¹ is —OH. In someembodiments, n is 7. In some embodiments, R³ and R⁴ can be —OH. In someembodiments, n is 7 and R³ is —OH. In one or more embodiments, n is 7and R⁴ is —OH. In some embodiments, n is 7 and R³ and R⁴ are —OH. Insome embodiments, n is 7 and R³ and R⁴ combine with the carbon atoms towhich they are attached to form an epoxide. The symbol

can represent a double bond between R³ and R⁴ when n is 7.

The difference between a compound of Formula I and a compound of FormulaII is the point of connection of the glycerol ester. In some preferredembodiments, the glycerol ester is unsubstituted. Accordingly, in somepreferred embodiments, the present disclosure provides compounds of theFormula I-A:

and Formula II-A:

wherein the variables m, n, q, r, R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹,R¹⁰, R¹¹, R¹² and R¹³ are defined as above for Formula I and Formula II.

Studies were carried out in order to identify compounds for coatingformulations which reduce the rate of water/mass loss in coatedagricultural products and for which the resulting coatings arepreferably substantially undetectable to the human eye and/or do nototherwise alter the physical appearance of the coated products. Forthese studies, mixtures (which were typically solid but in some caseswere oils) comprising compounds of Formula I and/or compounds of FormulaII and/or other additives (e.g., 1-monoacylglycerides, fatty acids,esters, amides, amines, thiols, carboxylic acids, ethers, aliphaticwaxes, alcohols, salts (inorganic and organic), or combinations thereof)were first formed. The mixtures were then dissolved in a solvent (e.g.,either ethanol or a water and ethanol mixture, for instance in a 1:2water:ethanol ratio or lower) to form a solution, from which coatingswere formed over a variety of edible substrates (blueberries, bananas,strawberries, lemons, avocados, and limes). Details about the specificformulations used and procedures for the forming of the coatings aredescribed below for illustrative purposes with reference to FIGS. 2-18.The substrates were then examined for the presence of visible residueson the surface and tested for percent mass loss over time, and werecompared to control samples without the coatings.

A variety of different compositions of mixtures (e.g., solid mixtures)were used to form coatings on a variety of edible substrates, where thespecific compositions and coating procedures are described below withreference to FIGS. 2-18. Some of the compositions were substantiallypure (e.g., at least 90% or at least 95% pure) 2-monoacylglyceridecompounds (e.g., compounds of Formula I). For example, coatings wereformed from compositions that were substantially pure PA-2G, as well asfrom compositions that were substantially pure SA-2G. Some of thecompositions were substantially pure (e.g., at least 90% or at least 95%pure) 1-monoacylglyceride compounds (e.g., compounds of Formula II). Forexample, coatings were formed from compositions that were substantiallypure PA-1G, compositions that were substantially pure OA-1G, andcompositions that were substantially pure SA-1G.

Some of the compositions included a compound of Formula I and anadditive, where for each of these compositions various ratios of thecompound of Formula I to the additive were tested. For example, coatingswere formed from compositions which included the combinations of acompound of Formula I and an additive as listed in Table 1 below.Additives included, for example, a saturated or unsaturated compound ofFormula II, a saturated or unsaturated fatty acid, an ethyl ester,and/or a second compound of Formula I which is different from the(first) compound of Formula I (e.g., has a different length carbonchain).

TABLE 1 Exemplary Coating Compositions Compound of Formula I AdditiveNote SA-2G SA-1G Additive is a saturated compound of Formula II(1-monoacylglyceride) with the same length carbon chain as the compoundof Formula I PA-2G PA-1G Additive is a saturated compound of Formula II(1-monoacylglyceride) with the same length carbon chain as the compoundof Formula I PA-2G MA-1G Additive is a saturated compound of Formula II(1-monoacylglyceride) with a shorter length carbon chain than thecompound of Formula I PA-2G OA-1G Additive is an unsaturated compound ofFor- mula II (1-monoacylglyceride) with a longer length carbon chainthan the compound of Formula I PA-2G SA-1G Additive is a saturatedcompound of Formula II (1-monoacylglyceride) with a longer length carbonchain than the compound of Formula I PA-2G PA Additive is a saturatedfatty acid with the same length carbon chain as the compound of FormulaI PA-2G OA Additive is an unsaturated fatty acid with a longer lengthcarbon chain than the compound of Formula I PA-2G SA Additive is asaturated fatty acid with a longer length carbon chain than the compoundof Formula I PA-2G MA Additive is a saturated fatty acid with a shorterlength carbon chain than the compound of Formula I PA-2G OA-2G Additiveis an unsaturated compound of For- mula I (2-monoacylglyceride) with alonger carbon chain than PA-2G PA-2G EtPA Additive is an ethyl ester.

In some embodiments, the compound of Formula I is PA-2G. In someembodiments, the compound of Formula I is PA-2G and the additive isPA-1G. In some embodiments, the compound of Formula I is PA-2G and theadditive is SA-1G. In some embodiments, the compound of Formula I isPA-2G and the additive is MA-1G. In some embodiments, the compound ofFormula I is PA-2G and the additive is OA-1G.

In some embodiments, the compound of Formula I is SA-2G. In someembodiments, the compound of Formula I is SA-2G and the additive isPA-1G. In some embodiments, the compound of Formula I is SA-2G and theadditive is SA-1G. In some embodiments, the compound of Formula I isSA-2G and the additive is MA-1G. In some embodiments, the compound ofFormula I is SA-2G and the additive is OA-1G.

In some embodiments, the compound of Formula I is MA-2G. In someembodiments, the compound of Formula I is MA-2G and the additive isPA-1G. In some embodiments, the compound of Formula I is MA-2G and theadditive is SA-1G. In some embodiments, the compound of Formula I isMA-2G and the additive is MA-1G. In some embodiments, the compound ofFormula I is MA-2G and the additive is OA-1G.

In some embodiments, the compound of Formula I is OA-2G. In someembodiments, the compound of Formula I is OA-2G and the additive isPA-1G. In some embodiments, the compound of Formula I is OA-2G and theadditive is SA-1G. In some embodiments, the compound of Formula I isOA-2G and the additive is MA-1G. In some embodiments, the compound ofFormula I is OA-2G and the additive is OA-1G.

In some embodiments of Formula I or Formula II, n is 0. In someembodiments, n is 1. In some embodiments, n is 2. In some embodiments, nis 3. In some embodiments, n is 4. In some embodiments, n is 5. In someembodiments, n is 6. In some embodiments, n is 7. In some embodiments, nis 8.

In some embodiments of Formula I or Formula II, m is 0. In someembodiments, m is 1. In some embodiments, m is 2. In some embodiments, mis 3.

In some embodiments of Formula I or Formula II, q is 0. In someembodiments, q is 1. In some embodiments, q is 2. In some embodiments, qis 3. In some embodiments, q is 4. In some embodiments, q is 5.

In some embodiments of Formula I or Formula II, r is 0. In someembodiments, r is 1. In some embodiments, r is 2. In some embodiments, ris 3. In some embodiments, r is 4. In some embodiments, r is 5. In someembodiments, r is 6. In some embodiments, r is 7. In some embodiments, ris 8.

In some embodiments, R^(a) is hydrogen. In some embodiments, R^(b) ishydrogen. In some embodiments, R^(a) and R^(b) are both hydrogen.

In some embodiments of compounds of Formula I, n is 8. In someembodiments, q is 1. In some embodiments, m is 1. In some embodiments, ris 1.

In some embodiments, compounds of Formula I or Formula II have between11 and 21 carbon atoms bonded to the carbonyl carbon (i.e., thecompounds are C₁₂-C₂₂ chains). In some embodiments, the compounds ofFormula I or Formula II are C₁₂, C₁₃, C₁₄, C₁₅, C₁₆, C₁₇, C₁₈, C₁₉, C₂₀,C₂₁, or C₂₂ chains.

In some embodiments of compounds of Formula I, n is 8 and q is 1. Insome embodiments, n is 8, q is 1 and m is 1. In some embodiments, n is8, q is 1, m is 1, and r is 1. In some embodiments, n is 8, q is 1, m is1, r is 1, and

represents a single bond.

In some embodiments of compounds of Formula I, m is 3. In someembodiments, n is 8, q is 1 and m is 3. In some embodiments, n is 8, qis 1, m is 3, and r is 1. In some embodiments, n is 8, q is 1, m is 3, ris 1, and

represents a single bond.

In some embodiments of compounds of Formula I, n is 6. In someembodiments, n is 6 and q is 1. In some embodiments, n is 6, q is 1 andm is 1. In some embodiments, n is 6, q is 1, m is 1, and r is 1. In someembodiments, n is 6, q is 1, m is 1, r is 1, and

represents a single bond.

In some embodiments of compounds of Formula I, n is 7. In someembodiments, n is 7 and q is 1. In some embodiments, n is 7, q is 1 andm is 3. In some embodiments, n is 7, q is 1, m is 3, and r is 1. In someembodiments, n is 7, q is 1, m is 3, r is 1, and

represents a cis double bond.

In some embodiments of compounds of Formula II, n is 8. In someembodiments, q is 1. In some embodiments, m is 1. In some embodiments, ris 1.

In some embodiments of compounds of Formula II, n is 8 and q is 1. Insome embodiments, n is 8, q is 1 and m is 1. In some embodiments, n is8, q is 1, m is 1, and r is 1. In some embodiments, n is 8, q is 1, m is1, r is 1, and

represents a single bond.

In some embodiments of compounds of Formula II, m is 3. In someembodiments, n is 8, q is 1 and m is 3. In some embodiments, n is 8, qis 1, m is 3, and r is 1. In some embodiments, n is 8, q is 1, m is 3, ris 1, and

represents a single bond.

In some embodiments of compounds of Formula II, n is 6. In someembodiments, n is 6 and q is 1. In some embodiments, n is 6, q is 1 andm is 1. In some embodiments, n is 6, q is 1, m is 1, and r is 1. In someembodiments, n is 6, q is 1, m is 1, r is 1, and

represents a single bond.

In some embodiments of compounds of Formula II, n is 7. In someembodiments, n is 7 and q is 1. In some embodiments, n is 7, q is 1 andm is 3. In some embodiments, n is 7, q is 1, m is 3, and r is 1. In someembodiments, n is 7, q is 1, m is 3, r is 1, and

represents a cis double bond.

For each of the coatings which were formed from solid mixtures whichcontained either a single compound of Formula I (i.e., PA-2G or SA-2G)or an additive (i.e., a compound of Formula II, including SA-1G, PA-1G,MA-1G, and OA-1G) but not a mixture of both, at most a nominal reductionin mass loss was observed for the coated edible substrates as comparedto the control samples (i.e., uncoated substrates). Furthermore, all ofthese coatings resulted in heavy levels of visible precipitates and/orother visible residues or features on the surfaces of the ediblesubstrates.

However, for coatings formed from solid mixtures which contained both acompound of Formula I and an additive, where the mass or molar ratio ofthe additive to the compound of Formula I was in a range of 0.1 to 1, asubstantial reduction in mass loss over time (e.g., as compared touncoated edible substrates, a reduction in the mass loss rate of atleast 20-30% for strawberries, finger limes, and avocados, and at least10-20% for blueberries) was observed for the coated edible substrates,and visible precipitates and/or other visible residues or features werenot observed or were substantially suppressed. This result was observedfor a wide variety of additives combined with a compound of Formula I,including all of the combinations listed in Table 1, as well as for avariety of different edible substrates, including blueberries, bananas,strawberries, lemons, avocados, and limes. The reduction in mass lossover time for substrates having coatings with this specific range ofmass ratios of the additives to the compounds of Formula I, accompaniedby the absence of visible precipitates/residues, was unexpected, inparticular since coatings formed from one of the compounds but not theother either did not produce such a large reduction in mass loss in thecoated substrates over time or also resulted in heavy visibleprecipitates and/or other visible residues or features on the surfacesof the substrates. Further details of the compounds, the solutions, thecoatings, the procedures for forming the coatings, and the results arepresented in the Figures and their associated descriptions below.

As described above, it was observed that for the solid mixtures whichwere a substantially pure compound of Formula I (e.g., at least 90%pure, at least 95% pure, or at least 99% pure), or contained thecompound of Formula I but at most only small amounts of the additive(e.g., the mass or molar ratio of the additive to the compound ofFormula I was less than 0.1 or 0.2 or 0.25, or the solid mixture was asubstantially pure mixture of the compound of Formula I), the protectivecoatings that were subsequently formed all tended to at least partiallyprecipitate or leave a visible residue on the surface of the substrate.As seen in FIG. 1, the residues were easily visible to the naked eye,creating the general appearance of a white, film-like substance overportions of the edible substrate, the portions each tending to be atleast 0.25 μm² in area, and in some cases at least 1 μm² in area, atleast 5 μm² in area, at least 10 μm² in area, at least 100 μm² in area,or at least 1000 μm² in area.

As also described above, similar residues were also observed forcoatings formed from solid mixtures which contained a compound ofFormula II but at most only small amounts of a compound of Formula I oranother additive (e.g., the solid mixture was a substantially puremixture of compound of Formula II, e.g., at least 90% pure, or onlyincluded small amounts of compounds of Formula I or an additive).However, these residues were not present, or were not visible to thenaked eye (i.e., if present were smaller than 0.25 μm² in area), inprotective coatings formed of compositions which were combinations ofFormula I compounds and an additive (e.g., Formula II, fatty acid,and/or ester compounds), where the mass ratio of the additive to thecompound of Formula I was greater than about 0.1 (e.g., greater thanabout 0.2 or between 0.2 and 1). In particular, the residues were notpresent, or were not visible to the naked eye, in protective coatingsformed of compositions including combinations of Formula I and FormulaII compounds, where the compositions were at least about 10% Formula Icompounds (e.g., at least 20% Formula I compounds) and at least 10%Formula II compounds (e.g., at least 20% Formula II compounds) by mass.

In some embodiments where the coatings are used to protect ediblesubstrates, the presence of the visible residues described above cancause the substrate to appear damaged or to have a less appealingphysical appearance to consumers, which may be undesirable. Thus, inmany cases, it is desirable for the coatings to be substantially free ofvisible residues, such that the coating is substantially transparent tolight in the visible range and the appearance of the substrate does notappear to be in any way modified from its natural state (e.g., when itis uncoated).

Without wishing to be bound by theory, it is believed that the compoundsof Formula I (i.e., the 2-monoacylglyceride compounds) in the solidmixtures, which were subsequently incorporated into the protectivecoatings, provided for the substantially improved beneficial qualitiesof the coatings (e.g., reduction in the mass loss rate of at least20-30% for strawberries, finger limes, and avocados, and at least 10-20%for blueberries) in a variety of edible substrates. However, too high aconcentration of compounds of Formula I caused portions of the coatingsto precipitate or otherwise leave visible residues. The presence of theresidues in the coatings often resulted in porous regions in thecoatings, thereby at least partially negating the beneficial propertiesof the coatings. Combining the compounds of Formula I with a smallerconcentration of additives (e.g., 1-monoacylglyceride, fatty acid,and/or ester compounds) in the solid mixtures prevented the visibleresidues from forming during subsequent formation of the coatings, whileat the same time allowing for protective coatings with the beneficialproperties described above to be formed. However, if the concentrationof compounds of Formula I in the solid mixture was too low (e.g., themass ratio of the additives to the compounds of Formula I was greaterthan 1, or the solid mixture was formed of the additive compoundswithout the compounds of Formula I), even in cases where visibleresidues were not observed or were less prevalent, the efficacy of theprotective coatings was substantially compromised.

As described above, the mass ratio or molar ratio of the additive to thecompound of Formula I can be in a range of about 0.1 to about 1. Forinstance, the range can be from about 0.2 to about 1; about 0.3 to about1; about 0.1 to about 0.5; from about 0.2 to about 0.4; from about 0.25to about 0.35; from about 0.3 to about 0.7; from about 0.4 to about 0.6;from about 0.2 to about 0.7; from about 0.5 to about 1; or from about0.45 to about 0.55. For instance, the molar ratio of the additive (e.g.,a compound of Formula II) to the compound of Formula I can be about 0.5,0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.6, 0.65, 0.7, 0.75,0.8, 0.85, 0.9, 0.95, 1, 1.5, 2, 2.5, 3, or greater. In someembodiments, the molar ratio can be about 0.25, about 0.3, 0.33, orabout 0.35.

Additional studies were carried out to examine coatings formed frommixtures that did not contain compounds of Formula I, but includedmultiple component mixtures of compounds of Formula II, fatty acids,and/or esters. For example, coatings were formed from compositions whichincluded the combinations of compounds of Formula II and one or moreadditives as listed in Table 2 below. Additives included, for example, asaturated or unsaturated fatty acid, an ethyl ester, and/or one or moreadditional compounds of Formula II which were different from the (first)compound of Formula II (e.g., have a different length carbon chain).

TABLE 2 Exemplary Coating Compositions (Optional) Component 1 Component2 Component 3 SA-1G MA (Fatty acid, shorter (Formula II) length carbonchain than compound of Formula II) SA-1G PA (Fatty acid, shorter(Formula II) length carbon chain than compound of Formula II) SA-1G SA(Fatty acid, same (Formula II) length carbon chain as compound ofFormula II) PA-1G MA (Fatty acid, shorter (Formula II) length carbonchain than compound of Formula II) PA-1G PA (Fatty acid, same (FormulaII) length carbon chain as compound of Formula II) PA-1G SA (Fatty acid,longer (Formula II) length carbon chain than compound of Formula II)MA-1G MA (Fatty acid, same (Formula II) length carbon chain as compoundof Formula II) MA-1G PA (Fatty acid, longer (Formula II) length carbonchain than compound of Formula II) MA-1G SA (Fatty acid, longer (FormulaII) length carbon chain than compound of Formula II) SA-1G (First PA-1G(Second compound of compound of Formula II, shorter carbon Formula II)chain than First compound of Formula II) SA-1G (First MA-1G (Secondcompound of compound of Formula II, shorter carbon Formula II) chainthan First compound of Formula II) MA-1G (First PA-1G (Second compoundof compound of Formula II, longer carbon Formula II) chain than Firstcompound of Formula II) SA-1G PA (Fatty acid, shorter OA (Fatty acid,same (Formula II) length carbon chain than length carbon chain ascompound of Formula II) compound of Formula II)

In one or more embodiments, the compositions described herein aresubstantially free of impurities such as proteins, polysaccharides,phenols, lignans, aromatic acids, terpenoids, flavonoids, carotenoids,alkaloids, alcohols, alkanes, and aldehydes. In one or more embodiments,compositions described herein contain less than about 10% (e.g., lessthan about 9%, less than about 8%, less than about 7%, less than about6%, less than about 5%, less than about 4%, less than about 3%, lessthan about 2%, or less than about 1%) of impurities such as proteins,polysaccharides, phenols, lignans, aromatic acids, terpenoids,flavonoids, carotenoids, alkaloids, alcohols, alkanes, and aldehydes.

In some embodiments, the compositions are substantially pure. Forinstance, the compound of Formula I and/or Formula II used in thecompositions can be greater than 90% pure. It can be, for instance,greater than 91% pure, greater than 92% pure, greater than 93% pure,greater than 94% pure, greater than 95% pure, greater than 96% pure,greater than 97% pure, greater than 98% pure, or greater than 99% pure.In some embodiments, the additive (e.g., Formula II, fatty acid, orester) can be greater than 90% pure. It can be, for instance, greaterthan 91% pure, greater than 92% pure, greater than 93% pure, greaterthan 94% pure, greater than 95% pure, greater than 96% pure, greaterthan 97% pure, greater than 98% pure, or greater than 99% pure.

While the compositions described herein can be dissolved in a solventprior to being applied to a substrate, the compositions may be providedwithout a solvent. In such embodiments, the compositions can be a solidmixture used in the form of a powder, e.g., a dry powder. The solidmixtures can, for example, be provided as a combination of compounds ofFormula I and an additive in the ratios previously described. Such solidmixtures (e.g., powders) can be formed having an average grain diameterof less than 2 millimeters. For instance, the solid mixtures can have anaverage grain diameter of 50 to 1,000 microns (e.g., 100 am, 200 am, 300am, 400 am, 500 am, 600 am, 700 am, 800 am or 900 am). Solid mixtureswith smaller average grain diameter, for instance in the range of 50 nmto 50 am, can be used as well. In some embodiments, control of theaverage grain size can provide advantages such as allowing for moreefficient dissolution of the mixture in a solvent.

In some embodiments, the composition of the disclosure can be providedin combination with and/or dissolved in a solvent. The composition canbe substantially soluble in a solvent, such as water, ethanol, or acombination of both. In some embodiments, a composition comprisingFormula I (e.g., a composition comprising a compound of Formula I andFormula II) can be soluble in water at a range of at least about 0.5mg/mL, at least about 1 mg/mL, at least about 5 mg/mL, at least about 10mg/mL, at least about 20 mg/mL, at least about 50 mg/mL, or at leastabout 100 mg/mL. In some embodiments, a composition comprising Formula I(e.g., a composition comprising a compound of Formula I and Formula II)can be soluble in ethanol at a range of at least about 1 mg/mL, at leastabout 5 mg/mL, at least about 10 mg/mL, at least about 20 mg/mL, atleast about 50 mg/mL, or at least about 100 mg/mL. In some embodiments,a composition comprising Formula I (e.g., a composition comprising acompound of Formula I and Formula II) can be soluble in a mixture ofwater and ethanol at a range of at least about 1 mg/mL, at least about 5mg/mL, at least about 10 mg/mL, at least about 20 mg/mL, at least about50 mg/mL, or at least about 100 mg/mL.

If the solvent is a combination of water and ethanol, the solvent can bein any ratio from 1:99 to 99:1. For instance, the solvent can be atleast 25% water by volume; at least 50% water by volume; at least 75%water by volume; or at least 90% water by volume. It is understood thatthe compositions disclosed herein may be substantially soluble (e.g.,100% soluble at a concentration of at least about 0.5 mg/mL, at leastabout 1 mg/mL, at least about 5 mg/mL, at least about 10 mg/mL, at leastabout 20 mg/mL, at least about 50 mg/mL, or at least about 100 mg/mL) inany of the solvents described herein. For instance, the compositions canbe substantially soluble in water or a combination of water and analcohol (e.g., ethanol). In addition to ethanol, the solvent can alsocomprise other organic alcohols such as methanol or isopropanol, or acombination of both. The solvent can also comprise organic solvents suchas acetone, ethyl acetate or tetrahydrofuran.

In some embodiments, a composition of the present disclosure (e.g., acomposition comprising a compound of Formula I and a compound of FormulaII) can be a solid at about 25° C. and about one atmosphere of pressure.In some embodiments, a compound of the present disclosure (e.g., acomposition comprising a compound of Formula I and a compound of FormulaII) can be a liquid or oil at about 25° C. and about one atmosphere ofpressure.

In preferred embodiments, the solvent is non-toxic for humanconsumption. In some embodiments, the solvent is not appreciablyabsorbed into the substrate when the substrate is coated with a mixtureof solvent and compounds of the disclosure. In some embodiments, thesolvent is used to dissolve the compounds and coat the substrate. Thesolvent can then evaporate, leaving the composition on the surface ofthe substrate. In some embodiments, the evaporation of solvent takesplace before the consumption of the substrate (e.g., food product) by aconsumer.

In some embodiments, prior to forming a protective coating over thesurface of the substrate, the solid compounds of the present disclosureare dissolved in a solvent (e.g., ethanol or a combination of ethanoland H₂O). Without wishing to be bound by theory, while the solidmixtures can be highly soluble (e.g., at least 90% soluble at aconcentration of at least about 0.5 mg/mL, at least about 1 mg/mL, atleast about 5 mg/mL, at least about 10 mg/mL, at least about 20 mg/mL,at least about 50 mg/mL, or at least about 100 mg/mL) in ethanol, manysolid mixtures containing an additive (e.g., 1-monoacylglycerides) and acompound of Formula I (e.g., 2-monoacylglycerides) at a respective massratio in the range of 0.1 to 1 were found to be highly soluble insolvents that were at least 25% water by volume, for examplecombinations of EtOH and H₂O which were as high as 40% H₂O by volume.For example, at or near room temperature (e.g., at a temperature in therange of 0° C. to 40° C., such as in the range of 15° C. to 35° C.), thesolubility limit of the solid mixture in a solvent that is at least 25%water by volume can be sufficiently high to allow for a solute (e.g.,compounds of Formula I and/or an additive) to solvent ratio of at least0.5 mg or 1 mg of solid mixture per milliliter of solvent, for example asolute to solvent ratio in the range of 1 to 20 mg or 0.5 to 100 mg ofsolid mixture per milliliter of solvent.

In some embodiments, a solid mixture that is highly soluble (e.g., atleast 90% soluble at a concentration of at least about 0.5 mg/mL, atleast about 1 mg/mL, at least about 5 mg/mL, at least about 10 mg/mL, atleast about 20 mg/mL, at least about 50 mg/mL, or at least about 100mg/mL) in a solvent with a high percentage of water can be beneficial byreducing the overall costs associated with forming the protectivecoatings, and can also allow for the use of a non-toxic solvent whichcan optionally be recycled.

The composition can be a solid at standard temperature and pressure(i.e., about 25° C. and about 1 atmosphere of pressure). In someembodiments, a composition of the disclosure (e.g., a compositioncomprising a compound of Formula I and a compound of Formula II) caninclude solid crystals having an average diameter of less than about 2millimeters (e.g., less than 1.5 millimeters, or less than 1millimeter).

In one or more embodiments, the compound of Formula I can be selectedfrom:

In one or more embodiments, the compound of Formula I can be selectedfrom:

In one or more embodiments, the compound of Formula II can be selectedfrom:

In one or more embodiments, the compound of Formula II can be selectedfrom:

The compounds and compositions of the present disclosure can bedissolved in a solvent before application to a substrate. In someembodiments, the mass ratio or molar ratio of the additive (e.g., acompound of Formula II) to the compound of Formula I is in a range of0.1 to 1, and wherein the additive and the compound of Formula I aredissolved in a solvent at a concentration of at least about 0.5 mg/mL.In some embodiments, the concentration of the composition in the solventis at least about 1 mg/mL. In some embodiments, the concentration of thecomposition in the solvent is at least about 5 mg/mL, at least about 10mg/mL, at least about 20 mg/mL, at least about 50 mg/mL, or at leastabout 100 mg/mL. In some embodiments, the solution of the composition inthe solvent is saturated or supersaturated. In some embodiments, theconcentration of the composition is below the saturation limit in thesolution. The dissolution can be performed at a temperature in the rangeof about 0° C. to about 40° C. (e.g., in the range of about 15° C. toabout 30° C.).

The composition can further comprise an additional agent selected from apigment or an odorant. In some embodiments, the additive is a compoundof Formula II.

The compounds and compositions described herein can be used as agents toreduce (e.g., prevent or diminish) food spoilage. For instance, thecompounds can be applied to the surface of a food product to supplementthe natural cutin barrier found in food products.

Without wishing to be bound by any theory, the coatings formed fromcompositions of the present disclosure can prevent or suppress waterloss (e.g., as compared to uncoated produce, reduce the mass loss rateby at least 20-30% for strawberries, finger limes, and avocados, and atleast 10-20% for blueberries) from the substrate via evaporation throughthe substrate surface, thereby reducing mass loss over time. Thecoatings formed from the compositions can also prevent oxidation viareaction with oxygen gas that comes into contact with the substrate. Thecoating can comprise a compound of Formula I along with an additive(e.g. a compound of Formula II). Accordingly, spoilage of, for instance,food or agricultural products is reduced because the chemical balance ofthe food product does not change significantly from the balance justbefore harvest (e.g., just before a food product is picked). Forexample, in some embodiments, coatings of the present disclosure canprevent oxidation (e.g., via ambient oxygen) of compounds that occurnaturally in the agricultural products by providing a barrier betweenatmospheric oxygen and the compounds. For example, in some embodimentsthe coatings can prevent moisture loss from the agricultural products byproviding a barrier between the moisture in the product and theatmosphere. Additionally, the coatings formed from the compounds of thedisclosure can protect a substrate such as a food or agriculturalproduct from pathogens such as bacteria, fungi or viruses by presentinga physical barrier between the pathogen and the substrate.

Factors that can affect how well the compositions are able to achievethese functions (e.g., how well the compositions are able to coat and/orprotect a substrate) include the specific composition of the precursorcompounds used to form the compositions, as well as the thickness,density, and uniformity of the coatings formed from the compositions. Inparticular, if the coating is non-uniform or includes regions where thecomposition has locally precipitated, the functionality of the resultingcoatings may be compromised.

In some embodiments, the composition (i.e., a mixture of a compound ofFormula I and an additive such as a compound of Formula II) is dissolvedin a solvent (e.g., water, ethanol, or a combination of both) andapplied to the surface of the substrate. The application of thecomposition can be accomplished by a number of different methods such asspraying, dipping, and the like. For instance, a harvest of fresh foodproduct (e.g., fruit) can be sprayed with a solution comprising asolvent (e.g., water, ethanol or a mixture of the two) and a compositionof the disclosure. Alternatively, the harvest can be submerged in asolution comprising a composition of the disclosure and filtered toseparate the food products from the solution.

In some embodiments, the coating of a food product is accomplished bycontacting the food product with a solution comprising a composition ofthe present disclosure and allowing the solvent to evaporate. Thecompositions (e.g., the compound of Formula I and the additive) are leftover on the surface of the food product after the solvent dries and thusform the coating.

In some embodiments, the solvent can be removed by mechanical means(e.g., dabbing or swabbing with a towel or other absorbent fabric orsurface). In some embodiments, the solvent can be dried by blowing airover the coated food products. In some embodiments, the solvent can bedried by application of a vacuum to the coated food products. In someembodiments, the solvent can be left to evaporate under ambientconditions (i.e., standard temperature and pressure). In the case wherethe substrate is dipped in a solution of compound and filtered, theresidual amounts of the composition of the disclosure that are leftafter filtration can be sufficient to coat the food product.

One of skill in the art will readily recognize that it can be possibleto use, for instance, desiccants and other tools known in the art toeffectively remove the solvent from freshly contacted (e.g., sprayed ordipped) substrate without disturbing the coating.

The compounds and solutions of the present disclosure can be applied toa substrate (e.g., a food product) before or after harvest of the foodproduct. For instance, solutions of the present disclosure can beapplied to a food product while the food product is still growing, orhas not yet been harvested (e.g., before the food product has beenpicked). Alternatively, the compounds of the present disclosure can beapplied after harvest. For instance, freshly picked fruit can beconsolidated in containers such as baskets and the solutions of thedisclosure can be applied to the fruit shortly after picking.

In some embodiments, the coatings can be undetectable to the human eye.Alternatively, the coating can be formed so as to have a visual qualitythat is aesthetically pleasing (e.g., to a consumer). For example, whenthe substrate is an edible substrate such as a fruit or a vegetable, itcan be preferable that the coating not modify the general appearance ofthe substrate surface to make the substrate more appealing.Alternatively, the coating can make the substrate appear shinier orbrighter and thus more aesthetically pleasing to the eye (e.g., to aconsumer).

As previously described, the coatings can form visible precipitates orother visible residues on the surface of a substrate upon application tothe substrate. Without wishing to be bound by any theory, visibleprecipitates or other visible residues larger than 0.25 square microns(0.25 μm²) in area can cause light in the visible spectrum to disperse,creating the appearance of a defect in the underlying substrate.Accordingly, for a given desired thickness of the coating, the specificcomposition as well as the method of application of the coating can beselected such that the resulting coating is substantially transparentand is substantially free of visible residues larger than 0.25 μm² inarea. In some embodiments, the coatings are substantially free of anyvisible residues formed from the compounds of Formula I and/or additive.In some embodiments, the visible residues are less than 0.25 μm² in area(e.g., less than 0.2 μm², less than 0.15 μm², or less than 0.1 μm²).Additionally, visible residues larger than 0.25 μm² in area can disturbthe coating such that portions of the substrate in some embodiments arenot fully covered and thus not fully protected. This can lead tomoisture loss, for instance, and accelerate spoilage.

In some embodiments, the coating can be formed so as to intentionallyalter the physical appearance of the substrate, for example to make thesubstrate appear shinier or brighter and thus more aestheticallypleasing to the eye (e.g., to a consumer), or to have the appearance ofa natural wax such as bloom on freshly picked blueberries. In thesecases, it may be preferable that the coatings include visible residueslarger than 0.25 μm² in area. In such embodiments, it may be preferablethat the areal density of visible residues larger than 0.25 μm² in areaover the surface be relatively small, so as to improve the physicalappearance of the substrate without substantially degrading the qualityof the coating. For example, the coating can include at least 10separate visible residues larger 0.25 μm² in area per square centimeterof the surface of the substrate.

The protective coatings can be applied at a thickness which causes themto decrease the percent mass loss of the substrates over time, ascompared to control samples without the coatings. In someimplementations, the protective coatings have an average thickness ofabout 0.1 microns. In some embodiments, the average thickness of thecoating can be at least 0.15 microns, at least 0.2 microns, or at least0.25 microns. In some embodiments, the coatings have a minimum thicknessof at least about 0.1 microns. In some embodiments, the coatings can besubstantially free of defects while also having an average thickness ofabout 0.4 microns or greater.

The protective coatings described herein can also be formedsubstantially thinner than other conventional edible coatings (e.g., waxcoatings) while still causing a substantial decrease in the rate of massloss of the coated produce (or other perishable substrate). For example,in some embodiments, coatings formed over produce by methods describedherein can be less than 3 microns thick, less than 2 microns thick, lessthan 1.5 microns thick, between 0.1 and 3 microns thick, or between 0.05and 2 microns thick, and can simultaneously reduce the rate of mass lossof the produce (as compared to similar uncoated produce at the samestate of ripening) by at least 5%, at least 10%, at least 15%, at least20%, at least 25%, at least 30%, at least 35%, or at least 40%.

The protective coatings may also be sufficiently optically transparentso as to prevent the coatings from being detectable by the human eye.For example, the coatings can have an average transmittance of at least60% (e.g., about 60%, at least 65%, at least 70%, at least 80%, at least85%, at least 90%, at least 95%, about 99% or about 100%) for light inthe visible range such as sunlight (i.e., the portion of the solarspectrum having a wavelength between 400 nanometers and 700 nanometers).As used herein, “transmittance” is defined as the ratio of transmittedlight power to incident light power. As used herein, “averagetransmittance” refers to the average value of the transmittance over theentire area of the coating. In some embodiments, the entire coating canin all regions have a transmittance of at least 60% (e.g., about 60%, atleast 65%, at least 70%, at least 80%, at least 85%, at least 90%, atleast 95%, about 99% or about 100%) for light in the visible range.Because transmittance typically decreases with coating thickness, thecoatings can be made thin enough to allow for sufficient transmittanceof visible light while still being thick enough to serve as a barrier tomass/moisture loss, as previously described. For example, the protectivecoatings have an average thickness of less than 2 microns, less than 1.5microns, less than 1 micron, or less than 0.5 microns.

The compounds of Formula I and/or Formula II may be prepared by methodsknown in the art of organic synthesis as set forth in part by thefollowing synthetic schemes and examples. In the schemes describedbelow, it is well understood that protecting groups for sensitive orreactive groups are employed where necessary in accordance with generalprinciples or chemistry. Protecting groups are manipulated according tostandard methods of organic synthesis (T. W. Greene and P. G. M. Wuts,“Protective Groups in Organic Synthesis”, Third edition, Wiley, New York1999). These groups are removed at a convenient stage of the compoundsynthesis using methods that are readily apparent to those skilled inthe art. The selection processes, as well as the reaction conditions andorder of their execution, shall be consistent with the preparation ofcompounds of Formula I.

Those skilled in the art will recognize if a stereocenter exists in thecompounds of Formula I and/or Formula II. Accordingly, the presentdisclosure includes both possible stereoisomers (unless specified in thesynthesis) and includes not only racemic compounds but the individualenantiomers and/or diastereomers as well. When a compound is desired asa single enantiomer or diastereomer, it may be obtained bystereospecific synthesis or by resolution of the final product or anyconvenient intermediate. Resolution of the final product, anintermediate, or a starting material may be affected by any suitablemethod known in the art. See, for example, “Stereochemistry of OrganicCompounds” by E. L. Eliel, S. H. Wilen, and L. N. Mander(Wiley-lnterscience, 1994).

The compounds described herein may be made from commercially availablestarting materials or synthesized using known organic, inorganic, and/orenzymatic processes.

In some embodiments, a compound of Formula I can be prepared from acompound of Formula III (where Formula III is a compound as previouslydefined) according to Scheme 1.

As shown in Scheme 1, glycerol ester compounds of Formula I (e.g., 1-24)can be prepared from the corresponding acid by protecting any hydroxygroups that may be present in the acid (e.g., Formula III). As shownabove in Scheme 1, hydroxy groups can be protected with any suitablehydroxy protecting group known in the art, for example a -TBS(tert-butyldimethylsilyl) protecting group. Esterification of theprotected acid with an appropriately protected glycerol derivative(e.g., 2-phenyl-1, 3-dioxan-5-ol) can be accomplished by stirring in thepresence of DMAP and DCC. Deprotection of the silyl protecting groupscan be accomplished with an appropriate agent such as hydrofluoric acidor tetrabutylammonium fluoride (TBAF). Finally, the glycerol group canbe deprotected using standard conditions, for instance, hydrogenation ortreatment with an acid.

A skilled artisan will understand the chemical synthesis procedures setforth herein can be adjusted as necessary. For instance, otherprotecting groups can be used to protect, e.g., the alcohol groups aswill be understood by one of skill in the art.

In some embodiments, the compound of Formula III is an acid and theconverting step comprises esterifying the acid of Formula III. In someembodiments, the compound of Formula III is an ester and the convertingstep comprises transesterifying the ester of Formula III. In someembodiments, the compound of Formula III is an amide and the convertingstep comprises transesterifying the amide of Formula III. In someembodiments, the converting step comprises treating the compound ofFormula III with an appropriate alcohol and base or acid. In someembodiments, the base is sodium hydroxide, lithium hydroxide, potassiumhydroxide, sodium carbonate, lithium carbonate, or potassium carbonate.In some embodiments, the step of converting a compound of Formula III toa compound of Formula II comprises treating the compound of Formula IIIwith an enzyme.

In some embodiments, the forming of the compositions and the subsequentformation of the coatings is carried out by multiple parties. Forexample, a supplier or manufacturer of compounds suitable for thecompositions described herein could form a solution comprising thecompounds dissolved in a solvent and provide (e.g., supply or sell) thesolution to a grower or distributor of produce. The grower ordistributor could then apply the solution to produce, for example bydipping the produce in the solution, spraying the solution onto theproduce, or brushing the solution onto the produce. The grower ordistributor could then cause the composition to re-solidify on thesurface of the produce to form the coating, for example by placing theproduce on a drying rack and allowing the solvent to evaporate (oralternatively by blow drying the produce), thereby allowing thecomposition to solidify and form a coating over the produce. That is,after applying the solution to the produce, the solvent can be removedin order to precipitate the composition over the produce. As anotherexample, a supplier or manufacturer of compounds suitable for thecompositions described herein could form a solid mixture (e.g., inpowder form) of the compounds and provide (e.g., supply or sell) thesolid mixture to a grower or distributor of produce. The grower ordistributor could then dissolve the solid mixture in a solvent to form asolution and apply the solution to produce, for example by dipping theproduce in the solution, spraying the solution onto the produce, orbrushing the solution onto the produce. The grower or distributor couldthen cause the composition to re-solidify on the surface of the produceto form the coating, for example by placing the produce on a drying rackand allowing the solvent to evaporate (or alternatively by blow dryingthe produce), thereby allowing the composition to solidify and form acoating over the produce.

In some cases where multiple parties are involved, the first party(e.g., the party that forms the solid compositions and/or solutions) mayoptionally provide instructions or recommendations about, for example,how to form solutions from the solid compositions, how to treat theproduce or other substrates, and/or how to cause the solvent to beremoved and the coatings to be formed. The instructions can, forexample, be provided in either written or oral form, and may indicateone or more of the following: (i) that solid compositions are to bedissolved in a solvent and then applied to a substrate; (ii) suitablesolvents in which to dissolve the solid compositions, as well assuitable concentrations for the solid compositions dissolved in thesolvent; (iii) suitable procedures for applying the solutions to thesubstrates; and/or (iv) suitable procedures for removing (e.g.,evaporating) the solvent and/or forming a coating over the surface ofthe substrate. While the instructions or recommendations can be suppliedby the first party directly with the solid compositions and/or solutions(e.g., on packaging in which the solid compositions and/or solutions arestored), the instructions or recommendations may alternatively besupplied separately, for example on a website owned or controlled by thefirst party, or in advertising or marketing material provided by or onbehalf of the first party.

In view of the above, it is recognized that in some cases, a party formsand/or provides solid compositions and/or solutions according to one ormore embodiments described herein (i.e., a first party) may not directlyapply the compositions/solutions to the substrates to form coatings, butcan instead direct (e.g., can instruct or request) a second party (orthird party) to apply the compositions/solutions to the substratesand/or to form coatings. That is, even if the first party does not applythe solution to a surface of the substrate, the first party may stillcause the solution to be applied to a surface of the substrate, forexample by providing instructions or recommendations as described above.Similarly, the first party can also cause the solvent to be removedand/or the composition to re-solidify on the surface to form thecoating, for example by providing instructions or recommendations to thesecond party on procedures for removing (e.g., evaporating) the solventand/or for allowing the composition to re-solidify on the surface toform the coating. Accordingly, as used herein, the act of applying acomposition or solution to a surface of a substrate can also includedirecting or instructing another party to apply the composition orsolution to the surface of the substrate, or causing the composition orsolution to be applied to the surface of the substrate. Additionally, asused herein, the act of causing a composition to re-solidify on thesurface of a substrate to form the coating can also include directing orinstructing another party to on how to cause the composition tore-solidify on the surface of a substrate to form the coating.

EXAMPLES

The disclosure is further illustrated by the following synthesis and useexamples, which are not to be construed as limiting this disclosure inscope or spirit to the specific procedures herein described. It is to beunderstood that the examples are provided to illustrate certainembodiments and that no limitation to the scope of the disclosure isintended thereby. It is to be further understood that resort may be hadto various other embodiments, modifications, and equivalents thereofwhich may suggest themselves to those skilled in the art withoutdeparting from the spirit of the present disclosure and/or scope of theappended claims.

All reagents and solvents were purchased and used without furtherpurification unless specified. Palmitic acid (98%) was purchased fromSigma-Aldrich. p-TsOH and MTBE were purchased from Alfa-Aesar. Toluene,Et₂O, and EtOAc were purchased from VDR. Lipozyme® TL IM lipase waspurchased from Novozymes. 10 wt % Pd/C was purchased from StremChemicals and used as received. All reactions were carried out under anatmosphere of air with non-dried solvents unless otherwise stated.Yields refer to chromatographically and spectroscopically (¹H NMR)homogeneous materials, unless otherwise stated. Reactions were monitoredby thin layer chromatography (TLC) carried out on 0.25 mm E. Mercksilica gel plates (60F-254) using UV light as the visualizing agent andan acidic mixture of anisaldehyde, ceric ammonium molybdate, or basicaqueous potassium permangante (KMnO₄), and heat as developing agents.NMR spectra were recorded on a Bruker Avance 500 MHz and/or Varian VNMRs600 MHz instruments and calibrated using residual un-deuterated solventas an internal reference (CHCl₃ at 7.26 ppm ¹H NMR, 77.16 ppm ¹³C NMR).The following abbreviations (or combinations thereof) were used toexplain the multiplicities: s=singlet, d=doublet, t=triplet, q=quartet,m=multiplet, br=broad. Mass spectra (MS) were recorded on a timeof-flight mass spectrometer by electrospray ionization (ESI) or fielddesorption (FD) at the UC Santa Barbara mass spectrometry facility.1,3-bis(benzyloxy)propan-2-ol was synthesized according to the procedureof Nemoto et al. (J. Org. Chem., 1992, 57, p. 435).

The following abbreviations are used in the following examples andthroughout the specification:

DCC=N,N′-Dicyclohexylcarbodiimide

DCM=dichloromethaneDMAP=Dimethylamino pyridine

DMF=N,N-dimethylformamide

MBTE=^(t)BME=tert-butylmethyl etherp-TsOH=para toluenesulfonic acidTBS=TBDPS=tert-butyldimethyl silyl

Example 1: Synthesis of 1,3-dihydroxypropan-2-yl Palmitate (3)

Step 1. 1,3-bis(benzyloxy)propan-2-yl palmitate (6)

70.62 g (275.34 mmole) of palmitic acid (5), 5.24 g (27.54 mmole) ofp-TsOH, 75 g (275.34 mmole) of 1,3-bis(benzyloxy)propan-2-ol, and 622 mLof toluene were charged into a round bottom flask equipped with a Tefloncoated magnetic stir bar. A Dean-Stark Head and condenser were attachedto the flask and a positive flow of N₂ was initiated. The flask washeated to reflux in a heating mantle while the reaction mixture wasstirred vigorously until the amount of water collected (˜5 mL) in theDean-Stark Head indicated full ester conversion (˜8 hr). The flask wasallowed to cool down to room temperature and the reaction mixture waspoured into a separatory funnel containing 75 mL of a saturated aqueoussolution of Na₂CO₃ and 75 mL of brine. The toluene fraction wascollected and the aqueous layer was extracted with 125 mL of Et₂O. Theorganic layers were combined and washed with 100 mL of brine, dried overMgSO₄, filtered and concentrated in vacuo. The crude colorless oil wasdried under high vacuum providing (135.6 g, 265.49 mmole, crudeyield=96.4%) of 1,3-bis(benzyloxy)propan-2-yl palmitate (6).

HRMS (ESI-TOF) (m/z): calcd. for C₃₃H₅₀O₄Na, [M+Na]⁺, 533.3607; found,533.3588;

¹H NMR (600 MHz, CDCl₃): δ 7.41-7.28 (m, 10H), 5.28 (p, J=5.0 Hz, 1H),4.59 (d, J=12.1 Hz, 2H), 4.54 (d, J=12.1 Hz, 2H), 3.68 (d, J=5.2 Hz,4H), 2.37 (t, J=7.5 Hz, 2H), 1.66 (p, J=7.4 Hz, 2H), 1.41-1.15 (m, 24H),0.92 (t, J=7.0 Hz, 3H) ppm.

¹³C NMR (151 MHz, CDCl₃): δ 173.37, 138.09, 128.43, 127.72, 127.66,73.31, 71.30, 68.81, 34.53, 32.03, 29.80, 29.79, 29.76, 29.72, 29.57,29.47, 29.40, 29.20, 25.10, 22.79, 14.23 ppm.

Step 2. 1,3-dihydroxypropan-2-yl palmitate (I-1)

7.66 g (15.00 mmole) of 1,3-bis(benzyloxy)propan-2-yl palmitate (6),79.8 mg (0.75 mmole) of 10 wt % Pd/C and 100 mL of EtOAc were charged toa 3 neck round bottom flask equipped with a Teflon coated magnetic stirbar. A cold finger, with a bubbler filled with oil attached to it, and abubbling stone connected to a 1:4 mixture of H₂/N₂ gas tank were affixedto the flask. H₂/N₂ was bubbled at 1.2 LPM into the flask until thedisappearance of both starting material and mono-deprotected substrateas determined by TLC (˜60 min). Once complete, the reaction mixture wasfiltered through a plug of Celite, which was then washed with 100 mL ofEtOAc. The filtrate was placed in a refrigerator at 4° C. for 24 hrs.The precipitate from the filtrate (white and transparent needles) wasfiltered and dried under high vacuum yielding (2.124 g, 6.427 mmole,yield=42.8%) of 1,3-dihydroxypropan-2-yl palmitate.

HRMS (FD-TOF) (m/z): calcd. for C₁₉H₃₈O₄, 330.2770; found, 330.2757;

¹H NMR (600 MHz, CDCl₃): δ 4.93 (p, J=4.7 Hz, 1H), 3.84 (t, J=5.0 Hz,4H), 2.37 (t, J=7.6 Hz, 2H), 2.03 (t, J=6.0 Hz, 2H), 1.64 (p, J=7.6 Hz,2H), 1.38-1.17 (m, 26H), 0.88 (t, J=7.0 Hz, 3H) ppm.

¹³C NMR (151 MHz, CDCl₃): δ 174.22, 75.21, 62.73, 34.51, 32.08, 29.84,29.83, 29.81, 29.80, 29.75, 29.61, 29.51, 29.41, 29.26, 25.13, 22.85,14.27 ppm.

Example 2—Synthesis of 1,3-dihydroxypropan-2-yl Palmitate by EnzymeCatalysis

3.66 g (4.50 mmole) of tripalmitin (7), 7.26 mg of Lipozyme® TL-IMlipase, 2.65 mL of EtOH, and 363 mL of MTBE were charged to a roundbottom flask equipped with a teflon coated magnetic stir bar. Thereaction mixture was stirred for 15 min at room temperature, filtered,and concentrated in vacuo. 15 mL of hexanes was added to the crudeproduct and the product/hexanes mixture was stored in a refrigerator at4° C. for 24 hrs. The crude mixture was filtered, washed with 30 mL ofcold hexanes, and dried under high vacuum yielding 1.256 g (3.8 mmole,yield=84.4%) of 1,3-dihydroxypropan-2-yl palmitate (I-1). (Note: yieldis based on total mass being from 1,3-dihydroxypropan-2-yl palmitate,however it contains 12.16 mole % (20 wt %) of diacylglycerol palmitate.)

HRMS (FD-TOF) (m/z): calcd. for C₁₉H₃₈O₄, 330.2770; found, 330.2757;

¹H NMR (600 MHz, CDCl₃): δ 4.93 (p, J=4.7 Hz, 1H), 3.84 (t, J=5.0 Hz,4H), 2.37 (t, J=7.6 Hz, 2H), 2.03 (t, J=6.0 Hz, 2H), 1.64 (p, J=7.6 Hz,2H), 1.38-1.17 (m, 26H), 0.88 (t, J=7.0 Hz, 3H) ppm.

¹³C NMR (151 MHz, CDCl₃): δ 174.22, 75.21, 62.73, 34.51, 32.08, 29.84,29.83, 29.81, 29.80, 29.75, 29.61, 29.51, 29.41, 29.26, 25.13, 22.85,14.27 ppm.

Example 3: Synthesis of 1,3-dihydroxypropan-2-yl octadecanoate

28.45 g (100 mmole) of stearic acid acid, 0.95 g (5 mmole) of p-TsOH,27.23 g (275.34 mmole) of 1,3-bis(benzyloxy)propan-2-ol, and 200 mL oftoluene were charged into a round bottom flask equipped with a Tefloncoated magnetic stir bar. A Dean-Stark Head and condenser were attachedto the flask and a positive flow of N₂ was initiated. The flask washeated to reflux in an oil bath while the reaction mixture was stirredvigorously until the amount of water collected (˜1.8 mL) in theDean-Stark Head indicated full ester conversion (˜16 hr). The flask wasallowed to cool down to room temperature and the solution was dilutedwith 100 mL of hexanes. The reaction mixture was poured into aseparatory funnel containing 50 mL of a saturated aqueous solution ofNa₂CO₃. The organic fraction was collected and the aqueous layer wasextracted twice more with 50 mL portions of hexanes. The organic layerswere combined and washed with 100 mL of brine, dried over MgSO₄,filtered and concentrated in vacuo. The crude colorless oil was furtherpurified by selective liquid-liquid extraction using hexanes andacetonitrile and the product was again concentrated in vacuo, yielding(43.96 g, 81.60 mmole, yield=81.6%) of 1,3-bis(benzyloxy)propan-2-ylstearate.

¹H NMR (600 MHz, CDCl₃): δ 7.36-7.27 (m, 10H), 5.23 (p, J=5.0 Hz, 1H),4.55 (d, J=12.0 Hz, 2H), 4.51 (d, J=12.1 Hz, 2H), 3.65 (d, J=5.0 Hz,4H), 2.33 (t, J=7.5 Hz, 2H), 1.62 (p, J=7.4 Hz, 2H), 1.35-1.22 (m, 25H),0.88 (t, J=6.9 Hz, 3H) ppm.

6.73 g (12.50 mmole) of 1,3-bis(benzyloxy)propan-2-yl stearate, 439 mg(0.625 mmole) of 20 wt % Pd(OH)₂/C and 125 mL of EtOAc were charged to a3 neck round bottom flask equipped with a Teflon coated magnetic stirbar. A cold finger, with a bubbler filled with oil attached to it, and abubbling stone connected to a 1:4 mixture of H₂/N₂ gas tank were affixedto the flask. H₂/N₂ was bubbled at 1.2 LPM into the flask until thedisappearance of both starting material and mono-deprotected substrateas determined by TLC (˜120 min). Once complete, the reaction mixture wasfiltered through a plug of Celite, which was then washed with 150 mL ofEtOAc. The filtrate was placed in a refrigerator at 4° C. for 48 hrs.The precipitate from the filtrate (white and transparent needles) wasfiltered and dried under high vacuum yielding (2.12 g, 5.91 mmole,yield=47.3%) of 1,3-dihydroxypropan-2-yl stearate.

LRMS (ESI+) (m/z): calcd. for C₂₁H₄₃O₄[M+H]⁺, 359.32; found 359.47;

¹H NMR (600 MHz, CDCl₃): δ 4.92 (p, J=4.7 Hz, 1H), 3.88-3.78 (m, 4H),2.40-2.34 (m, 2H), 2.09 (t, J=6.2 Hz, 2H), 1.64 (p, J=7.3 Hz, 2H), 1.25(s, 25H), 0.88 (t, J=7.0 Hz, 3H) ppm.

¹³C NMR (151 MHz, CDCl₃): δ 174.32, 75.20, 62.63, 34.57, 32.14, 29.91,29.89, 29.87, 29.82, 29.68, 29.57, 29.47, 29.33, 25.17, 22.90, 14.32ppm.

FIGS. 2-18 illustrate the effects of coating a variety of ediblesubstrates with the compositions described herein. To form the coatings,solid mixtures of the compositions were first fully dissolved in ethanolat a concentration of 10 mg/mL (except where a different concentrationis specified) to form a solution. The solution was then applied to thesubstrate either by spraying or dip coating, as detailed for each of thesubstrates below. The substrates were then dried on drying racks underambient conditions (temperature in the range of 23° C.-27° C., humidityin the range of 40%-55%) until all of the solvent had evaporated,allowing the coatings to form over the substrates. The resultantcoatings each had a thickness in the range of about 0.5 μm to 1 μm. Forall mixtures described, PA was purchased from Sigma Aldrich, PA-1G waspurchased from Tokyo Chemical Industry Co, PA-2G was prepared followingthe method of Example 1 above, SA was purchased from Sigma Aldrich,SA-1G was purchased from Alfa Aesar, SA-2G was prepared following themethod of Example 3 above, MA was purchased from Sigma Aldrich, MA-1Gwas purchased from Tokyo Chemical Industry Co, OA was purchased fromSigma Aldrich, and EtPA was purchased from Sigma Aldrich.

Example 3—Effect of Compositions Comprising 1- and 2-Monoacylglycerideson Lemons

FIG. 2 shows the effects of mass loss over time observed in lemons overthe course of 3 weeks, both for uncoated lemons and for lemons whichwere coated with a composition described herein. The compositionincluded PA-2G (compound of Formula I) and PA-1G (additive). The massratio and molar ratio of the PA-1G to PA-2G was about 0.33 (i.e., amolar ratio of about 25:75). The PA-2G was prepared following the methodof Example 1 above. The composition was dissolved in ethanol at aconcentration of 10 mg/mL to form a solution, and the solution wasapplied to the surface of the lemons to form the coatings.

In order to form the coatings, the lemons were placed in a bag, and thesolution containing the composition was poured into the bag. The bag wasthen sealed and lightly agitated until the entire surface of each lemonwas wet. The lemons were then removed from the bag and allowed to dry ondrying racks under ambient room conditions at a temperature in the rangeof about 23° C.-27° C. and humidity in the range of about 40%-55%. Novisible residues or other visible precipitates were observed on thecoated lemons.

The lemons were held at these same temperature and humidity conditionsfor the entire duration of the time they were tested for mass loss. 202is a high resolution photograph of an uncoated lemon immediately afterbeing picked (Day 1), and 204 is a high resolution photograph of a lemonimmediately after being picked and coated on the same day. 212 and 214are photographs of the uncoated and coated lemons, respectively, takenon Day 22, 21 days after photographs 202 and 204. In order to bettervisualize the cross-sectional area loss (which is directly related tomass loss), an overlay 222 of the outline of the untreated lemon on Day1 is shown around 212, and an overlay 224 of the outline of theuntreated lemon on Day 1 is shown around 214. The coated lemons had across sectional area greater than 90% of their original area (i.e.,greater than 92% of their original area), whereas the uncoated lemonshad a cross sectional area less than 80% of their original area (i.e.,about 78% of their original area).

FIG. 3 shows plots for both coated (302) and uncoated (304) lemonsindicating the reduction in cross sectional area as a function of timeover a period of 20 days. Specifically, on each day, high resolutionimages of each of the lemons were taken and analyzed with imageprocessing software (as in FIG. 2) to determine the ratio of the crosssectional area on the particular day to the initial cross sectional areaof the lemon. As seen in FIG. 3, after 20 days, the coated lemons had across sectional area greater than 90% of their original area (in factgreater than 92% of their original area), whereas the uncoated lemonshad a cross sectional area less than 80% of their original area.

Example 4—Effect of Compositions Comprising 1- and 2-Monoacylglycerideson Strawberries

FIG. 4 is a graph showing average daily mass loss rates for strawberriescoated with various mixtures of PA-2G (compound of Formula I) and PA-1G(additive) measured over the course of 4 days. Each bar in the graphrepresents average daily mass loss rates for a group of 15 strawberries.The strawberries corresponding to bar 402 were uncoated (control group).The strawberries corresponding to bar 404 were coated with a mixturethat was substantially pure PA-1G. The strawberries corresponding to bar406 were coated with a mixture that was about 75% PA-1G and 25% PA-2G bymass (mass ratio and molar ratio of PA-1G to PA-2G was about 3). Thestrawberries corresponding to bar 408 were coated with a mixture thatwas about 50% PA-1G and 50% PA-2G by mass (mass ratio and molar ratio ofPA-1G to PA-2G was about 1). The strawberries corresponding to bar 410were coated with a mixture that was about 25% PA-1G and 75% PA-2G bymass (mass ratio and molar ratio of PA-1G to PA-2G was about 0.33). Thestrawberries corresponding to bar 412 were coated with a mixture thatwas substantially pure PA-2G. The compositions were each dissolved inethanol at a concentration of 10 mg/mL to form a solution, and thesolution was applied to the surface of the strawberries to form thecoatings.

In order to form the coatings, the strawberries were spray coatedaccording to the following procedures. First, the strawberries wereplaced on drying racks. Solutions containing each of the coatingcompositions were placed in spray bottles which generated a fine mistspray. For each bottle, the spray head was held approximately six inchesfrom the strawberries, and the strawberries were sprayed and thenallowed to dry on the drying racks. The strawberries were kept underambient room conditions at a temperature in the range of about 23°C.-27° C. and humidity in the range of about 40%-55% while they driedand for the entire duration of the time they were tested.

As shown in FIG. 4, the uncoated strawberries (402) exhibited an averagemass loss rate of greater than 7.5% per day. The mass loss rates of thestrawberries coated with the substantially pure PA-1G formulation (404)and the substantially pure PA-2G formulation (412) exhibited averagedaily mass loss rates between 6% and 6.5%, which was nominally betterthan the uncoated strawberries (402). However, the strawberries coatedwith substantially pure PA-1G or substantially pure PA-2G formulations(404 and 412, respectively) all exhibited heavy residues on theirsurfaces. The strawberries corresponding to bar 406 (PA-1G to PA-2G massratio of about 3) exhibited slightly improved mass loss rates, slightlyless than 6% per day, but still exhibited moderate residues on theirsurfaces. The strawberries corresponding to bars 408 and 410 (PA-1G toPA-2G mass ratios of about 1 and 0.33, respectively) exhibitedsubstantially improved mass loss rates; the strawberries correspondingto bar 408 exhibited average daily mass loss rates of just over 5%,while the strawberries corresponding to bar 410 exhibited average dailymass loss rates of under 5%, with none of the strawberries in either ofthese groups exhibiting visible residues on their surfaces.

FIG. 5 shows high resolution photographs of 4 coated and 4 uncoatedstrawberries over the course of 5 days at the temperature and humidityconditions described above, where the coated strawberries were coatedwith mixtures having a PA-1G to PA-2G mass ratio and molar ratio ofabout 0.33 (i.e., about 25:75) as in bar 410 in FIG. 4. As seen, theuncoated strawberries began to exhibit fungal growth and discolorationby day 3, and were mostly covered in fungus by day 5. In contrast, thecoated strawberries did not exhibit any fungal growth by day 5 and werelargely similar in overall color and appearance on day 1 and day 5.

Example 5—Effect of Compositions Comprising 1- and 2-Monoacylglycerideson Blueberries

FIG. 6 is a graph showing average daily mass loss rates for blueberriescoated with various mixtures of PA-2G (compound of Formula I) and PA-1G(additive) measured over the course of several days. Each bar in thegraph represents average daily mass loss rates for a group of 60blueberries. The blueberries corresponding to bar 602 were uncoated(control group). The blueberries corresponding to bar 604 were coatedwith a mixture that was substantially pure PA-1G. The blueberriescorresponding to bar 606 were coated with a mixture that was about 75%PA-1G and 25% PA-2G by mass (i.e., the mass ratio and molar ratio ofPA-1G to PA-2G was about 3). The blueberries corresponding to bar 608were coated with a mixture that was about 50% PA-1G and 50% PA-2G bymass (i.e., the mass ratio and molar ratio of PA-1G to PA-2G was about1). The blueberries corresponding to bar 610 were coated with a mixturethat was about 25% PA-1G and 75% PA-2G by mass (mass ratio and molarratio of PA-1G to PA-2G was about 0.33). The blueberries correspondingto bar 612 were coated with a mixture that was substantially pure PA-2G.The compositions were each dissolved in ethanol at a concentration of 10mg/mL to form a solution, and the solution was applied to the surface ofthe blueberries to form the coatings.

In order to form the coatings, the blueberries were placed in bags, andthe solution containing the composition was poured into the bag. The bagwas then sealed and lightly agitated until the entire surface of eachblueberry was wet. The blueberries were then removed from the bag andallowed to dry on drying racks. The blueberries were kept under ambientroom conditions at a temperature in the range of about 23° C.-27° C. andhumidity in the range of about 40%-55% while they dried and for theentire duration of the time they were tested.

As shown in FIG. 6, the uncoated blueberries (602) exhibited an averagemass loss rate of nearly 2.5% per day. The mass loss rates of theblueberries coated with the substantially pure PA-1G formulation (604)and the substantially pure PA-2G formulation (612), as well as theblueberries corresponding to bars 606 (PA-1G to PA-2G ratio of about 3)and 608 (PA-1G to PA-2G ratio of about 1) exhibited average daily massloss rates between 2.1% and 2.3%, which was nominally better than theuncoated blueberries (602). However, the blueberries coated withsubstantially pure PA-1G or substantially pure PA-2G formulations (604and 612, respectively) all exhibited heavy residues on their surfaces,and the blueberries corresponding to bar 606 (PA-1G to PA-2G mass ratioof about 3) exhibited moderate residues on their surfaces. Theblueberries corresponding to bar 610 (PA-1G to PA-2G mass ratios ofabout 0.33) exhibited mass loss rates under 2%, which was a substantialimprovement over the uncoated blueberries (602), and also did notexhibit any visible residues on their surfaces.

FIG. 7 is a graph showing average daily mass loss rates for blueberriescoated with various mixtures of SA-2G (compound of Formula I) and SA-1G(additive) measured over the course of several days. Each bar in thegraph represents average daily mass loss rates for a group of 60blueberries. The blueberries corresponding to bar 702 were uncoated(control group). The blueberries corresponding to bar 704 were coatedwith a mixture that was substantially pure SA-1G. The blueberriescorresponding to bar 706 were coated with a mixture that was about 75%SA-1G and 25% SA-2G by mass (mass ratio and molar ratio of SA-1G toSA-2G was about 3). The blueberries corresponding to bar 708 were coatedwith a mixture that was about 50% SA-1G and 50% SA-2G by mass (massratio and molar ratio of SA-1G to SA-2G was about 1). The blueberriescorresponding to bar 710 were coated with a mixture that was about 25%SA-1G and 75% SA-2G by mass (mass ratio and molar ratio of SA-1G toSA-2G was about 0.33). The blueberries corresponding to bar 712 werecoated with a mixture that was substantially pure SA-2G. Thecompositions were each dissolved in ethanol at a concentration of 10mg/mL to form a solution, and the solution was applied to the surface ofthe blueberries to form the coatings.

In order to form the coatings, the blueberries were placed in bags, andthe solution containing the composition was poured into the bag. The bagwas then sealed and lightly agitated until the entire surface of eachblueberry was wet. The blueberries were then removed from the bag andallowed to dry on drying racks. The blueberries were kept under ambientroom conditions at a temperature in the range of about 23° C.-27° C. andhumidity in the range of about 40%-55% while they dried and for theentire duration of the time they were tested.

As shown in FIG. 7, the results for SA-1G/SA-2G mixtures were similar tothose for PA-1G/PA-2G mixtures. The uncoated blueberries (702) exhibitedan average mass loss rate of about 2.4% per day. The mass loss rates ofthe blueberries coated with the substantially pure SA-1G formulation(704) and the substantially pure SA-2G formulation (712), as well as theblueberries corresponding to bars 706 (SA-1G to SA-2G ratio of about 3)and 708 (SA-1G to SA-2G ratio of about 1) exhibited average daily massloss rates between 2.1% and 2.2%, which was nominally better than theuncoated blueberries (702). However, the blueberries coated withsubstantially pure SA-1G or substantially pure SA-2G formulations (704and 712, respectively) all exhibited heavy residues on their surfaces,and the blueberries corresponding to bar 706 (SA-1G to SA-2G mass ratioof about 3) exhibited moderate residues on their surfaces. Theblueberries corresponding to bar 710 (SA-1G to SA-2G mass ratios ofabout 0.33) exhibited average mass loss rates of about 1.8%, which was asubstantial improvement over the uncoated blueberries (702), and alsodid not exhibit any visible residues on their surfaces.

FIG. 8, which illustrates the results of another blueberry study, showsplots of the percent mass loss over the course of 5 days in uncoatedblueberries (802), blueberries coated using a first solution of 10 mg/mLof compounds dissolved in ethanol (804), and blueberries coated using asecond solution of 20 mg/mL of compounds dissolved in ethanol (806). Thecompounds in both the first and second solutions included a mixture ofPA-1G and PA-2G, where the mass ratio and molar ratio of PA-1G to PA-2Gwas about 0.33 (i.e., a ratio of 25:75 as with bar 610 in FIG. 6). Toform the coatings over the coated blueberries, the following dip coatingprocedures were used. Each blueberry was picked up with a set oftweezers and individually dipped in the solution for approximately 1second or less, after which the blueberry was placed on a drying rackand allowed to dry. The blueberries were kept under ambient roomconditions at a temperature in the range of about 23° C.-27° C. andhumidity in the range of about 40%-55% while they dried and for theentire duration of the time they were tested. Mass loss was measured bycarefully weighing the blueberries each day, where the reported percentmass loss was equal to the ratio of mass reduction to initial mass. Asshown, the percent mass loss for uncoated blueberries was almost 20%after 5 days, whereas the percent mass loss for blueberries coated withthe 10 mg/mL solution was less than 15% after 5 days, and the percentmass loss for blueberries coated with the 20 mg/mL solution was lessthan 10% after 5 days.

FIG. 9 shows high resolution photographs of the uncoated blueberries(802) from the study in FIG. 8, and of the blueberries coated with the10 mg/mL solution of a 25:75 mass ratio and molar ratio (i.e., 0.33) ofPA-1G to PA-2G (804) from the study of FIG. 8, taken at day 5. The skinsof the uncoated blueberries 802 were highly wrinkled as a result of massloss of the blueberries, whereas the skins of the coated blueberriesremained very smooth.

Example 6—Effect of Compositions Comprising 1- and 2-Monoacylglycerideson Bananas

FIG. 10 shows high resolution photographs of coated and uncoated bananasover the course of 14 days, where the coatings were formed from acomposition dissolved in a solvent. The composition included PA-2G(compound of Formula I) and PA-1G (additive). The mass ratio and molarratio of the PA-1G to PA-2G was about 0.33 (i.e., about 25:75). Thecomposition was dissolved in ethanol at a concentration of 10 mg/mL toform a solution, and the solution was applied to the surface of thelemons to form the coatings.

In order to form the coatings, the bananas were placed in a bag, and thesolution containing the composition was poured into the bag. The bag wasthen sealed and lightly agitated until the entire surface of each bananawas wet. The bananas were then removed from the bag and allowed to dryon drying racks under ambient room conditions at a temperature in therange of about 23° C.-27° C. and humidity in the range of about 40%-55%.The bananas were held at these same temperature and humidity conditionsfor the entire duration of the time they were tested. As shown, thecoatings clearly served as an effective barrier to oxidation, therebypreventing discoloration of the bananas and slowing down the ripeningprocess. For example, for the uncoated banana, over 30% of the peel wasa light brown color at Day 6, over 80% of the peel was a light browncolor at Day 9, and almost the entire peel was a darker brown color byDay 14. On the other hand, for the coated banana, only slight browningand discoloration were observed even by Day 14.

Example 7—Effect of Compositions Comprising 1- and 2-Monoacylglycerideson Finger Limes

FIG. 11 is a graph showing average daily mass loss rates for fingerlimes coated with various mixtures of PA-2G (compound of Formula I) andPA-1G (additive) measured over the course of several days. Each bar inthe graph represents average daily mass loss rates for a group of 24finger limes. The finger limes corresponding to bar 1102 were uncoated(control group). The finger limes corresponding to bar 1104 were coatedwith a mixture that was substantially pure PA-1G. The finger limescorresponding to bar 1106 were coated with a mixture that was about 75%PA-1G and 25% PA-2G by mass (mass ratio and molar ratio of PA-1G toPA-2G was about 3). The finger limes corresponding to bar 1108 werecoated with a mixture that was about 50% PA-1G and 50% PA-2G by mass(mass ratio and molar ratio of PA-1G to PA-2G was about 1). The fingerlimes corresponding to bar 1110 were coated with a mixture that wasabout 25% PA-1G and 75% PA-2G by mass (mass ratio and molar ratio ofPA-1G to PA-2G was about 0.33). The finger limes corresponding to bar1112 were coated with a mixture that was substantially pure PA-2G. Thecompositions were each dissolved in ethanol at a concentration of 10mg/mL to form a solution, and the solution was applied to the surface ofthe finger limes to form the coatings.

In order to form the coatings, the finger limes were placed in bags, andthe solution containing the composition was poured into the bag. The bagwas then sealed and lightly agitated until the entire surface of eachfinger lime was wet. The finger limes were then removed from the bag andallowed to dry on drying racks. The finger limes were kept under ambientroom conditions at a temperature in the range of about 23° C.-27° C. andhumidity in the range of about 40%-55% while they dried and for theentire duration of the time they were tested.

As shown in FIG. 11, the uncoated finger limes (1102) exhibited anaverage mass loss rate of over 5% per day. The mass loss rates of thefinger limes coated with the substantially pure PA-1G formulation (1104)and the substantially pure PA-2G formulation (1112) exhibited averagedaily mass loss rates of just over 4% and just under 4%, respectively,which was nominally better than the uncoated finger limes (1102).However, the finger limes coated with substantially pure PA-1G orsubstantially pure PA-2G formulations (1104 and 1112, respectively) allexhibited heavy residues on their surfaces. The finger limescorresponding to bar 1106 (75:25 mass ratio of PA-1G to PA-2G, or a massratio of about 3) showed improved results, yielding an average dailymass loss rate of less than 3.5% but still exhibiting moderate residueson their surfaces. The finger limes corresponding to bars 1108 and 1110(PA-1G to PA-2G mass ratios of about 1 (50:50) and 0.33 (25:75),respectively) exhibited mass loss rates under 3.5% and under 2.6%,respectively, which was a substantial improvement over the uncoatedfinger limes (1102), and also did not exhibit any visible residues ontheir surfaces.

Example 8—Effect of Compositions Comprising 1- and 2-Monoacylglycerideson Avocados

FIG. 12 is a graph showing the shelf life factor for avocados coatedwith various mixtures of PA-2G (compound of Formula I) and a1-monoacylglyceride additive (bars 1202, 1204, and 1206 are for MA-1G;bars 1212, 1214, and 1216 are for PA-1G; bars 1222, 1224, and 1226 arefor SA-1G). As used herein, the term “shelf life factor” is defined asthe ratio of the average mass loss rate of uncoated produce (measuredfor a control group) to the average mass loss rate of the correspondingcoated produce. Hence a larger shelf life factor corresponds to agreater reduction in average mass loss rate. Bars 1202, 1212, and 1222correspond to a 25:75 mixture of 1-monoacylglycerides to PA-2G (molarratio of 1-monoacylglycerides to PA-2G of about 0.33). Bars 1204, 1214,and 1224 correspond to a 50:50 mixture of 1-monoacylglycerides to PA-2G(molar ratio of 1-monoacylglycerides to PA-2G of about 1). Bars 1206,1216, and 1226 correspond to a 75:25 mixture of 1-monoacylglycerides toPA-2G (molar ratio of 1-monoacylglycerides to PA-2G of about 3).

Each bar in the graph represents a group of 30 avocados. All coatingswere formed by dipping the avocados in a solution comprising theassociated mixture dissolved in substantially pure ethanol at aconcentration of 5 mg/mL, placing the avocados on drying racks, andallowing the avocados to dry under ambient room conditions at atemperature in the range of about 23° C.-27° C. and humidity in therange of about 40%-55%. The avocados were held at these same temperatureand humidity conditions for the entire duration of the time they weretested.

As seen, for both the MA-1G/PA-2G and SA-1G/PA-2G combinations, thegreatest shelf life factor was achieved for a 1-monoacylglyceride toPA-2G molar ratio of about 0.33. Furthermore, for both of thesecombinations, the avocados coated with the 25:75 (i.e., molar ratio ofabout 0.33) and 50:50 (i.e., a molar ratio of about 1) molar ratiomixtures did not exhibit any visible residues on their surfaces, whereasthe avocados with 75:25 mixtures exhibited moderate to heavy residues.For the case of the PA-1G/PA-2G combinations, although the shelf lifefactor for the avocados coated with the 75:25 mixture was greater thanthat of the avocados coated with the 25:75 mixture, the avocados coatedwith the 75:25 mixture exhibited moderate to heavy residues, whereas theavocados coated with the 25:75 and 50:50 mixtures exhibited no visibleresidues. Although not shown, no coatings formed of any mixturescontaining only a single constituent of any of the compounds illustratedin FIG. 12 were undetectable to the human eye.

Example 9—Effect of Compositions Comprising 2-Monoacylglycerides andAdditives on Avocados

FIG. 13 is a graph showing the shelf life factor for avocados coatedwith various mixtures of PA-2G (compound of Formula I) and a fatty acidadditive (bars 1302, 1304, and 1306 are for MA; bars 1312, 1314, and1316 are for PA; bars 1322, 1324, and 1326 are for SA). Bars 1302, 1312,and 1322 correspond to a 25:75 mixture of fatty acid to PA-2G (molarratio of fatty acid to PA-2G of about 0.33). The mass ratios are about0.23, 0.25, and 0.28, respectively. Bars 1304, 1314, and 1324 correspondto a 50:50 mixture of fatty acid to PA-2G (molar ratio of fatty acid toPA-2G of about 1). The mass ratios are about 0.35, 0.39, and 0.43,respectively. Bars 1306, 1316, and 1326 correspond to a 75:25 mixture offatty acid to PA-2G (molar ratio of fatty acid to PA-2G of about 3). Themass ratios are about 2.1, 2.3, and 2.6, respectively.

Each bar in the graph represents a group of 30 avocados. All coatingswere formed by dipping the avocados in a solution comprising theassociated mixture dissolved in substantially pure ethanol at aconcentration of 5 mg/mL, placing the avocados on drying racks, andallowing the avocados to dry under ambient room conditions at atemperature in the range of about 23° C.-27° C. and humidity in therange of about 40%-55%. The avocados were held at these same temperatureand humidity conditions for the entire duration of the time they weretested.

As seen, for all three of these combinations, the greatest shelf lifefactor was achieved for a fatty acid to PA-2G molar ratio of about 0.33.Furthermore, for all of these combinations, the avocados coated with the25:75 and 50:50 molar ratio mixtures did not exhibit any visibleresidues on their surfaces, whereas the avocados with 75:25 mixturesexhibited moderate to heavy residues. Although not shown, no coatingsformed of any mixtures containing only a single constituent of any ofthe compounds illustrated in FIG. 13 were undetectable to the human eye.

FIG. 14 is a graph showing the shelf life factor for avocados coatedwith various other compounds. Each bar in the graph represents a groupof 30 avocados. All coatings were formed by dipping the avocados in asolution comprising the associated mixture dissolved in substantiallypure ethanol at a concentration of 5 mg/mL, placing the avocados ondrying racks, and allowing the avocados to dry under ambient roomconditions at a temperature in the range of about 23° C.-27° C. andhumidity in the range of about 40%-55%. The avocados were held at thesesame temperature and humidity conditions for the entire duration of thetime they were tested.

Bars 1401-1403 correspond to mixtures of PA-2G (compound of Formula I)with ethyl palmitate as an additive. Bars 1411-1413 correspond tomixtures of PA-2G (compound of Formula I) with oleic acid (unsaturatedfatty acid) as an additive. Bars 1401 and 1411 correspond to a 25:75mixture of additive to PA-2G (molar ratio of additive to PA-2G of about0.33). The mass ratios are both about 0.86. Bars 1402 and 1412correspond to a 50:50 mixture of additive to PA-2G (molar ratio ofadditive to PA-2G of about 1). The mass ratios both are about 0.43. Bars1403 and 1413 correspond to a 75:25 mixture of additive to PA-2G (molarratio of additive to PA-2G of about 3). The mass ratios are both about2.58. As seen for the combinations of PA-2G and EtPA as well as for thecombinations of PA-2G and OA, the greatest shelf life factor wasachieved with additive to PA-2G molar ratio of about 0.33.

Bars 1421-1423, 1431-1433, and 1441-1443 correspond to coatings formedof a compound of Formula II (e.g., a 1-monoacylglyceride) and anadditive (e.g., a fatty acid). Bars 1421-1423 correspond to mixtures ofSA-1G (compound of Formula II) with myristic acid as an additive. Bars1431-1433 correspond to mixtures of SA-1G (compound of Formula II) withpalmitic acid as an additive. Bars 1441-1443 correspond to mixtures ofSA-1G (compound of Formula II) with stearic acid as an additive. Bars1421, 1431, and 1441 correspond to a 25:75 mixture of fatty acid toSA-1G (molar ratio of fatty acid to SA-1G of about 0.33). The massratios are about 0.21, 0.23, and 0.26, respectively. Bars 1422, 1432,and 1442 correspond to a 50:50 mixture of fatty acid to SA-1G (molarratio of fatty acid to SA-1G of about 1). The mass ratios are about0.32, 0.35, and 0.40, respectively. Bars 1423, 1443, and 1443 correspondto a 75:25 mixture of fatty acid to SA-1G (molar ratio of fatty acid toSA-1G of about 3). The mass ratios are about 1.89, 2.13, and 2.37,respectively. As seen for all three of these combinations, the greatestshelf life factor was achieved for a fatty acid to SA-1G molar ratio ofabout 0.33.

Still referring to FIG. 14, while the largest shelf life factors forcombinations of SA-1G and a fatty acid were observed for an additive toSA-1G molar ratio of about 0.33, the additive to SA-1G molar ratiocorresponding to the least amount of residues on the surface was about42:58 for each of the combinations. The same was found to also be truefor coatings formed of other combinations of fatty acids and1-monoacylglycerides, for which results are shown in FIG. 15. For thevarious combinations of fatty acids and 1-monoacylglycerides that weretested, some always exhibited some level of residues, while for somethere was a very narrow range of ratios for which visible residues werenot observed. However, without wishing to be bound by theory, becausethe formation of residues is sensitive to changes in drying conditions(e.g., temperature and pressure), having such a narrow process windowlikely results in lower reproducibility in terms of suppressing visibleresidues over a wide range of drying conditions.

FIG. 15 is a graph showing the shelf life factor for avocados eachcoated with a mixture including a compound of Formula II and a fattyacid additive. All mixtures were a 1:1 mix by mole ratio of the compoundof Formula II and the fatty acid. Bars 1501-1503 correspond to coatingswith MA-1G as the compound of Formula II and MA (1501), PA (1502), andSA (1503) as the fatty acid additive. The mass ratios are about 1.32,1.18, and 1.06, respectively. Bars 1511-1513 correspond to coatings withPA-1G as the compound of Formula II and MA (1511), PA (1512), and SA(1513) as the fatty acid additive. The mass ratios are about 1.44, 1.29,and 1.16, respectively. Bars 1521-1523 correspond to coatings with SA-1Gas the compound of Formula II and MA (1521), PA (1522), and SA (1523) asthe fatty acid additive. The mass ratios are about 1.57, 1.39, and 1.25,respectively. Each bar in the graph represents a group of 30 avocados.All coatings were formed by dipping the avocados in a solutioncomprising the associated mixture dissolved in substantially pureethanol at a concentration of 5 mg/mL, placing the avocados on dryingracks, and allowing the avocados to dry under ambient room conditions ata temperature in the range of about 23° C.-27° C. and humidity in therange of about 40%-55%. The avocados were held at these same temperatureand humidity conditions for the entire duration of the time they weretested.

As shown, the shelf life factor tended to increase as the carbon chainlength of the 1-monoacylglyceride was increased. For example, allmixtures having a 1-monoacylglyceride with a carbon chain length greaterthan 13 exhibited a shelf life factor great than 1.2, all mixtureshaving a 1-monoacylglyceride with a carbon chain length greater than 15exhibited a shelf life factor great than 1.35, and all mixtures having a1-monoacylglyceride with a carbon chain length greater than 17 exhibiteda shelf life factor great than 1.6.

FIG. 16 is a graph showing the shelf life factor for avocados eachcoated with a mixture including two different compounds of Formula II,mixed at a 1:1 mole ratio, where for each mixture the 2 compounds ofFormula II have a different length carbon chain. Bar 1602 corresponds toa mixture of SA-1G (C18) and PA-1G (C16), bar 1604 corresponds to amixture of SA-1G (C18) and MA-1G (C14), and bar 1606 corresponds to amixture of PA-1G (C16) and MA-1G (C14). Each bar in the graph representsa group of 30 avocados. All coatings were formed by dipping the avocadosin a solution comprising the associated mixture dissolved insubstantially pure ethanol at a concentration of 5 mg/mL, placing theavocados on drying racks, and allowing the avocados to dry under ambientroom conditions at a temperature in the range of about 23° C.-27° C. andhumidity in the range of about 40%-55%. The avocados were held at thesesame temperature and humidity conditions for the entire duration of thetime they were tested. As shown, the PA-1G/MA-1G mixture (1606) resultedin a shelf life factor greater than 1.4, the SA-1G/PA-1G mixture (1602)resulted in a shelf life factor greater than 1.5, and the SA-1G/MA-1Gmixture (1604) resulted in a shelf life factor of about 1.6.

FIGS. 17 and 18 are graphs showing the shelf life factor for avocadoscoated with binary or ternary compound mixtures. Each bar in both graphsrepresents a group of 30 avocados. All coatings were formed by dippingthe avocados in a solution comprising the associated mixture dissolvedin substantially pure ethanol at a concentration of 5 mg/mL, placing theavocados on drying racks, and allowing the avocados to dry under ambientroom conditions at a temperature in the range of about 23° C.−27° C. andhumidity in the range of about 40%-55%. The avocados were held at thesesame temperature and humidity conditions for the entire duration of thetime they were tested.

The study illustrated in FIG. 17 was directed to examining the effectsof adding a second additive to a mixture including a compound of FormulaI and a first additive (the first additive being different from thesecond additive) in order to reduce the relative amount of the compoundof Formula I in the mixture while still maintaining an effective coatingwith no visible precipitates or other visible residues. Because in someembodiments compounds of Formula I can be more expensive to produce andcan be less stable (e.g., can convert to other types of compounds overtime due to equilibrium driving forces) than other types of compounds(e.g., fatty acids and compounds of Formula II), reducing the relativecomposition of the compound of Formula I in the mixture can in someembodiments reduce the cost as well as increase the stability of themixture.

Bar 1702 corresponds to avocados coated with a mixture including SA-1G(first additive, compound of Formula II) and PA-2G (compound of FormulaI) mixed at a mass ratio of 30:70 (28:72 molar ratio). This coatingresulted in a shelf life factor of about 1.6, and the coating was alsofree of any visible precipitates or other visible residues. Bar 1704corresponds to avocados coated with a mixture including SA-1G, PA-2G,and PA mixed at a respective mass ratio of 30:50:20 (27:48:25 molarratio). That is, as compared to the compounds corresponding to bar 1702,the coating formulation of bar 1704 could be formed by removing aportion of the PA-2G in the formulation corresponding to bar 1702 andreplacing it with PA, such that the formulation of bar 1704 was 50%compounds of Formula I (by mass) and 50% additives (by mass) (48:52molar ratio). As shown, the shelf life factor is only reduced slightly(as compared to bar 1702) to about 1.55, and the coating was found to befree of visible precipitates and other visible residues. Bar 1706corresponds to avocados coated with a mixture including SA-1G, PA-2G,and PA mixed at a respective mass ratio of 30:30:40 (i.e., removingadditional PA-2G and replacing it with PA) (25:27:47 molar ratio). Inthis case, the formulation was only 30% compounds of Formula I (by mass)and 70% additives (by mass) (27:73 molar ratio). As shown, although theshelf life factor is reduced (as compared to bars 1702 and 1704) toabout 1.43, this coating formulation was still highly effective atreducing the rate of mass loss in avocados, and the coating was alsofound to be free of visible precipitates and other visible residues.

As previously described, 2-component mixtures which lacked a compound ofFormula I could be made which resulted in coatings that reduced moistureloss and were also free of visible precipitates and other visibleresidues. However, in some embodiments the process window for thesemixtures can be narrow, and small variations in composition, conditionsduring drying, or other process variables tended to result in theformation of visible precipitates or residues. FIG. 18 illustrates theresults of a study directed to forming coatings with 3-componentmixtures that lacked a compound of Formula I, and for which a wide rangeof composition variations could still result in coatings which providedan effective barrier to moisture loss while at the same time being freeof visible precipitates and other visible residues. Bar 1802 correspondsto avocados coated with a mixture including SA-1G (compound of FormulaII) and PA (first fatty acid) mixed at a mass ratio of 50:50 (42:58molar ratio). The shelf life factor for these avocados was about 1.47.Although the coatings did not form any visible precipitates or othervisible residues, small variations from this 50:50 mass ratio were foundto cause visible precipitates/residues.

Bar 1804 corresponds to avocados coated with a mixture including SA-1G,OA, and PA mixed at a respective mass ratio of 45:10:45 (37:11:52 molarratio). That is, as compared to the compounds corresponding to bar 1802,the coating formulation of bar 1804 could be formed by removing equalportions (by mass) of the SA-1G and PA in the formulation of bar 1802and replacing them with OA. The shelf life factor for these avocados wasstill greater than 1.4, and no visible precipitates or other residuescould be detected. Furthermore, this combination was substantially lesssensitive to variations in formulation composition and processconditions as compared to the binary compound mixture of bar 1802;modest variations in composition or process conditions did not result information of visible precipitates or other visible residues, and thewater barrier properties of the coatings were maintained.

Bar 1806 corresponds to avocados coated with a mixture including SA-1G,OA, and PA mixed at a respective mass ratio of 40:20:40 (33:21:46 molarratio). That is, as compared to the compounds corresponding to bar 1804,the coating formulation of bar 1804 could be formed by further removingequal portions (by mass) of the SA-1G and PA in the formulation of bar1804 and replacing them with OA. The shelf life factor for theseavocados was greater than 1.3, and no visible precipitates or otherresidues could be detected. Furthermore, as with the combination of bar1804, this combination was substantially less sensitive to variations informulation composition and process conditions as compared to the binarycompound mixture of bar 1802; modest variations in composition orprocess conditions did not result in formation of visible precipitatesor other visible residues, and the water barrier properties of thecoatings were maintained

EQUIVALENTS

Various implementations of the compositions and methods have beendescribed above. However, it should be understood that they have beenpresented by way of example only, and not limitation. Where methods andsteps described above indicate certain events occurring in certainorder, those of ordinary skill in the art having the benefit of thisdisclosure would recognize that the ordering of certain steps may bemodified and such modification are in accordance with the variations ofthe disclosure. The implementations have been particularly shown anddescribed, but it will be understood that various changes in form anddetails may be made. Accordingly, other implementations are within thescope of the following claims.

1. A method of protecting harvested produce, comprising: providing amixture comprising a composition in a solvent; and applying the mixtureto a surface of the harvested produce to form a coating over theproduce, the coating being formed from the composition and being lessthan 3 microns thick; wherein the coating serves to reduce a rate ofmass loss of the harvested produce by at least 10%.
 2. The method ofclaim 1, wherein the coating is greater than 0.05 microns thick.
 3. Themethod of claim 2, wherein the composition comprises a compound selectedfrom the group consisting of monoacylglycerides, fatty acids, esters,amides, amines, thiols, carboxylic acids, ethers, aliphatic waxes,alcohols, organic salts, and inorganic salts.
 4. The method of claim 3,wherein the composition comprises a monoacylglyceride.
 5. The method ofclaim 4, wherein the composition further comprises an organic salt. 6.The method of claim 1, wherein the solvent comprises water or ethanol.7. The method of claim 1, wherein the composition comprises a firstmonoacylglyceride compound and a second monoacylglyceride compounddifferent from the first monoacylglyceride compound.
 8. The method ofclaim 7, wherein a carbon chain length of the first monoacylglyceridecompound is different from a carbon chain length of the secondmonoacylglyceride compound.
 9. The method of claim 8, wherein thecomposition further comprises an organic salt.
 10. A method ofprotecting an agricultural product, comprising: providing a solutioncomprising a composition dissolved in a solvent, the compositioncomprising at least one of 1-monoacylglycerides, 2-monoacylglycerides,fatty acids, esters, and organic salts; applying the solution to asurface of the agricultural product; and removing the solvent toprecipitate the composition and form a protective coating over theagricultural product, the coating being less than 3 microns thick;wherein the coating serves to reduce a rate of mass loss of theharvested produce by at least 10%; and the coating is substantially freeof visible residues.
 11. The method of claim 10, wherein the compositioncomprises a 1-monoacylglyceride having a first carbon chain length and a2-monoacylglyceride having a second carbon chain length different fromthe first carbon chain length.
 12. The method of claim 10, wherein thecomposition comprises a first 1-monoacylglyceride having a first carbonchain length and a second 1-monoacylglyceride having a second carbonchain length different from the first carbon chain length.
 13. Themethod of claim 12, wherein the composition comprises an organic salt.14. The method of claim 12, wherein the solution comprises a carboxylicacid.